x86-32, mm: Remove duplicated #include

b40827fa added an include
directive which is needless and is taken care of by a previous
one. Remove it.

Caught-by: Jaswinder Singh Rajput <jaswinderlinux@gmail.com>
Signed-off-by: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jaswinder Singh Rajput <jaswinderlinux@gmail.com>
Cc: H. Peter Anvin <hpa@linux.intel.com>
LKML-Reference: <20101025162523.GA4712@a1.tnic>
Signed-off-by: Ingo Molnar <mingo@elte.hu>