__vunmap doesn't seem to be used outside of mm/vmalloc.c, and has
no prototype in any header so let's make it static
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>