Make __vunmap static

__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: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/vmalloc.c

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index faa2a52..d3a9c53 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -311,7 +311,7 @@
 	return v;
 }
 
-void __vunmap(void *addr, int deallocate_pages)
+static void __vunmap(void *addr, int deallocate_pages)
 {
 	struct vm_struct *area;