MIPS: Loongson: clean up the coding style

With the help of script/checkpatch.pl, i have cleaned up the coding
style.

1. remove un-needed header files and tune some comments.
2. remove some un-needed { }

add a new header file loongson.h:

3. move some common header files to loongson.h
4. move some common extern declartions to loongson.h

and this new header file is needed for future loongson2f support.

Signed-off-by: Wu Zhangjin <wuzj@lemote.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/lemote/lm2e/env.c b/arch/mips/lemote/lm2e/env.c
index 9e88409..b9ef503 100644
--- a/arch/mips/lemote/lm2e/env.c
+++ b/arch/mips/lemote/lm2e/env.c
@@ -17,12 +17,10 @@
  * Free Software Foundation;  either version 2 of the  License, or (at your
  * option) any later version.
  */
-
-#include <linux/io.h>
-#include <linux/init.h>
-
 #include <asm/bootinfo.h>
 
+#include <loongson.h>
+
 unsigned long bus_clock, cpu_clock_freq;
 unsigned long memsize, highmemsize;