[PATCH] uml: kill some useless vmalloc tlb flushing

There is absolutely no reason to flush the kernel's VM area during a
tlb_flush_mm.

This results in a noticable performance increase in the kernel build
benchmark.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>