vmalloc: remove confusing comment on vwrite()

KM_USER1 is never used for vwrite() path so the caller doesn't need to
guarantee it is not used.  Only the caller should guarantee is KM_USER0
and it is commented already.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index fc77ada..5d60302 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -2003,8 +2003,6 @@
  *	should know vmalloc() area is valid and can use memcpy().
  *	This is for routines which have to access vmalloc area without
  *	any informaion, as /dev/kmem.
- *
- *	The caller should guarantee KM_USER1 is not used.
  */
 
 long vwrite(char *buf, char *addr, unsigned long count)