Clean up SIMD glue code

The SIMD glue code has gotten a bit #ifdef heavy so clean it up by having
one file for each possible SIMD arch. This also allows a simplification of
the x86_64 code as SSE/SSE2 is always known to exist on that arch.


git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@49 632fc199-4ca6-4c93-a231-07263d6284db
diff --git a/Makefile.am b/Makefile.am
index 57081f7..0e7ae4d 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -10,14 +10,17 @@
 	jddctmgr.c jdhuff.c jdinput.c jdmainct.c jdmarker.c jdmaster.c \
 	jdmerge.c jdphuff.c jdpostct.c jdsample.c jdtrans.c jerror.c \
 	jfdctflt.c jfdctfst.c jfdctint.c jidctflt.c jidctfst.c jidctint.c \
-	jidctred.c jquant1.c jquant2.c jutils.c jmemmgr.c jmemnobs.c \
-	jsimd.c
+	jidctred.c jquant1.c jquant2.c jutils.c jmemmgr.c jmemnobs.c
 
 if WITH_SIMD
 
 SUBDIRS = simd
 libjpeg_la_LIBADD = simd/libsimd.la
 
+else
+
+libjpeg_la_SOURCES += jsimd_none.c
+
 endif
 
 TSTHDRS = turbojpeg.h rrutil.h rrtimer.h