UniCore32-bugfix: Remove definitions in asm/bug.h to solve difference between native and cross compiler

For kernel/bound.c being compiled by native compiler, it will generate following errors in gcc 4.4.3:
  CC      kernel/bounds.s
In file included from include/linux/bug.h:4,
                 from include/linux/page-flags.h:9,
                 from kernel/bounds.c:9:
arch/unicore32/include/asm/bug.h:22: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'void'
arch/unicore32/include/asm/bug.h:23: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'void'

So, we moved definitions in asm/bug.h to arch/unicore32/kernel/setup.h to solve the problem.
Signed-off-by: NGuan Xuetao <gxt@mprc.pku.edu.cn>

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: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NGuan Xuetao <gxt@mprc.pku.edu.cn>