Disintegrate asm/system.h for Unicore32 [based on ver #3, changed by gxt]

Disintegrate asm/system.h for Unicore32. (Compilation successful)
The implementation details are not changed, but only splitted.
BTW, some codestyles are adjusted.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Guan Xuetao <gxt@mprc.pku.edu.cn>
diff --git a/arch/unicore32/mm/alignment.c b/arch/unicore32/mm/alignment.c
index 28f576d..de7dc5f 100644
--- a/arch/unicore32/mm/alignment.c
+++ b/arch/unicore32/mm/alignment.c
@@ -24,6 +24,8 @@
 #include <asm/tlbflush.h>
 #include <asm/unaligned.h>
 
+#include "mm.h"
+
 #define CODING_BITS(i)	(i & 0xe0000120)
 
 #define LDST_P_BIT(i)	(i & (1 << 28))	/* Preindex             */