Use consistent/modern code formatting for pointers

The convention used by libjpeg:

    type * variable;

is not very common anymore, because it looks too much like
multiplication.  Some (particularly C++ programmers) prefer to tuck the
pointer symbol against the type:

    type* variable;

to emphasize that a pointer to a type is effectively a new type.
However, this can also be confusing, since defining multiple variables
on the same line would not work properly:

    type* variable1, variable2;  /* Only variable1 is actually a
                                    pointer. */

This commit reformats the entirety of the libjpeg-turbo code base so
that it uses the same code formatting convention for pointers that the
TurboJPEG API code uses:

    type *variable1, *variable2;

This seems to be the most common convention among C programmers, and
it is the convention used by other codec libraries, such as libpng and
libtiff.
diff --git a/jsimd_none.c b/jsimd_none.c
index 65e3f8f..90dc965 100644
--- a/jsimd_none.c
+++ b/jsimd_none.c
@@ -103,19 +103,20 @@
 }
 
 GLOBAL(void)
-jsimd_h2v2_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,
+jsimd_h2v2_downsample (j_compress_ptr cinfo, jpeg_component_info *compptr,
                        JSAMPARRAY input_data, JSAMPARRAY output_data)
 {
 }
 
 GLOBAL(void)
-jsimd_h2v2_smooth_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,
-                       JSAMPARRAY input_data, JSAMPARRAY output_data)
+jsimd_h2v2_smooth_downsample (j_compress_ptr cinfo,
+                              jpeg_component_info *compptr,
+                              JSAMPARRAY input_data, JSAMPARRAY output_data)
 {
 }
 
 GLOBAL(void)
-jsimd_h2v1_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,
+jsimd_h2v1_downsample (j_compress_ptr cinfo, jpeg_component_info *compptr,
                        JSAMPARRAY input_data, JSAMPARRAY output_data)
 {
 }
@@ -139,24 +140,24 @@
 }
 
 GLOBAL(void)
-jsimd_int_upsample (j_decompress_ptr cinfo, jpeg_component_info * compptr,
-                      JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr)
+jsimd_int_upsample (j_decompress_ptr cinfo, jpeg_component_info *compptr,
+                      JSAMPARRAY input_data, JSAMPARRAY *output_data_ptr)
 {
 }
 
 GLOBAL(void)
 jsimd_h2v2_upsample (j_decompress_ptr cinfo,
-                     jpeg_component_info * compptr,
+                     jpeg_component_info *compptr,
                      JSAMPARRAY input_data,
-                     JSAMPARRAY * output_data_ptr)
+                     JSAMPARRAY *output_data_ptr)
 {
 }
 
 GLOBAL(void)
 jsimd_h2v1_upsample (j_decompress_ptr cinfo,
-                     jpeg_component_info * compptr,
+                     jpeg_component_info *compptr,
                      JSAMPARRAY input_data,
-                     JSAMPARRAY * output_data_ptr)
+                     JSAMPARRAY *output_data_ptr)
 {
 }
 
@@ -174,17 +175,17 @@
 
 GLOBAL(void)
 jsimd_h2v2_fancy_upsample (j_decompress_ptr cinfo,
-                           jpeg_component_info * compptr,
+                           jpeg_component_info *compptr,
                            JSAMPARRAY input_data,
-                           JSAMPARRAY * output_data_ptr)
+                           JSAMPARRAY *output_data_ptr)
 {
 }
 
 GLOBAL(void)
 jsimd_h2v1_fancy_upsample (j_decompress_ptr cinfo,
-                           jpeg_component_info * compptr,
+                           jpeg_component_info *compptr,
                            JSAMPARRAY input_data,
-                           JSAMPARRAY * output_data_ptr)
+                           JSAMPARRAY *output_data_ptr)
 {
 }
 
@@ -230,13 +231,13 @@
 
 GLOBAL(void)
 jsimd_convsamp (JSAMPARRAY sample_data, JDIMENSION start_col,
-                DCTELEM * workspace)
+                DCTELEM *workspace)
 {
 }
 
 GLOBAL(void)
 jsimd_convsamp_float (JSAMPARRAY sample_data, JDIMENSION start_col,
-                      FAST_FLOAT * workspace)
+                      FAST_FLOAT *workspace)
 {
 }
 
@@ -259,17 +260,17 @@
 }
 
 GLOBAL(void)
-jsimd_fdct_islow (DCTELEM * data)
+jsimd_fdct_islow (DCTELEM *data)
 {
 }
 
 GLOBAL(void)
-jsimd_fdct_ifast (DCTELEM * data)
+jsimd_fdct_ifast (DCTELEM *data)
 {
 }
 
 GLOBAL(void)
-jsimd_fdct_float (FAST_FLOAT * data)
+jsimd_fdct_float (FAST_FLOAT *data)
 {
 }
 
@@ -286,14 +287,14 @@
 }
 
 GLOBAL(void)
-jsimd_quantize (JCOEFPTR coef_block, DCTELEM * divisors,
-                DCTELEM * workspace)
+jsimd_quantize (JCOEFPTR coef_block, DCTELEM *divisors,
+                DCTELEM *workspace)
 {
 }
 
 GLOBAL(void)
-jsimd_quantize_float (JCOEFPTR coef_block, FAST_FLOAT * divisors,
-                      FAST_FLOAT * workspace)
+jsimd_quantize_float (JCOEFPTR coef_block, FAST_FLOAT *divisors,
+                      FAST_FLOAT *workspace)
 {
 }
 
@@ -322,28 +323,28 @@
 }
 
 GLOBAL(void)
-jsimd_idct_2x2 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
+jsimd_idct_2x2 (j_decompress_ptr cinfo, jpeg_component_info *compptr,
                 JCOEFPTR coef_block, JSAMPARRAY output_buf,
                 JDIMENSION output_col)
 {
 }
 
 GLOBAL(void)
-jsimd_idct_4x4 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
+jsimd_idct_4x4 (j_decompress_ptr cinfo, jpeg_component_info *compptr,
                 JCOEFPTR coef_block, JSAMPARRAY output_buf,
                 JDIMENSION output_col)
 {
 }
 
 GLOBAL(void)
-jsimd_idct_6x6 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
+jsimd_idct_6x6 (j_decompress_ptr cinfo, jpeg_component_info *compptr,
                 JCOEFPTR coef_block, JSAMPARRAY output_buf,
                 JDIMENSION output_col)
 {
 }
 
 GLOBAL(void)
-jsimd_idct_12x12 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
+jsimd_idct_12x12 (j_decompress_ptr cinfo, jpeg_component_info *compptr,
                   JCOEFPTR coef_block, JSAMPARRAY output_buf,
                   JDIMENSION output_col)
 {
@@ -368,21 +369,21 @@
 }
 
 GLOBAL(void)
-jsimd_idct_islow (j_decompress_ptr cinfo, jpeg_component_info * compptr,
+jsimd_idct_islow (j_decompress_ptr cinfo, jpeg_component_info *compptr,
                   JCOEFPTR coef_block, JSAMPARRAY output_buf,
                   JDIMENSION output_col)
 {
 }
 
 GLOBAL(void)
-jsimd_idct_ifast (j_decompress_ptr cinfo, jpeg_component_info * compptr,
+jsimd_idct_ifast (j_decompress_ptr cinfo, jpeg_component_info *compptr,
                   JCOEFPTR coef_block, JSAMPARRAY output_buf,
                   JDIMENSION output_col)
 {
 }
 
 GLOBAL(void)
-jsimd_idct_float (j_decompress_ptr cinfo, jpeg_component_info * compptr,
+jsimd_idct_float (j_decompress_ptr cinfo, jpeg_component_info *compptr,
                   JCOEFPTR coef_block, JSAMPARRAY output_buf,
                   JDIMENSION output_col)
 {
@@ -395,7 +396,7 @@
 }
 
 GLOBAL(JOCTET*)
-jsimd_huff_encode_one_block (void * state, JOCTET *buffer, JCOEFPTR block,
+jsimd_huff_encode_one_block (void *state, JOCTET *buffer, JCOEFPTR block,
                              int last_dc_val, c_derived_tbl *dctbl,
                              c_derived_tbl *actbl)
 {