[PATCH] Add const to pointer qualifiers for __chk_user_ptr and __chk_io_ptr.

Change prototypes for __chk_user_ptr and __chk_io_ptr to take const
void* instead of void*, so that code can pass "const void *" to them.

(Right now sparse does not warn about passing const void* to void*
functions, but that is a separate bug that I believe Josh is working on,
and once sparse does check this, the changed prototypes will be
necessary.)
Signed-off-by: Russ Cox <rsc@swtch.com>
Signed-off-by: Josh Triplett <josh@freedesktop.org>
Acked-by: Christopher Li <sparse@chrisli.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/linux/compiler.h

@@ -15,8 +15,8 @@
 # define __acquire(x)	__context__(x,1)
 # define __release(x)	__context__(x,-1)
 # define __cond_lock(x,c)	((c) ? ({ __acquire(x); 1; }) : 0)
-extern void __chk_user_ptr(void __user *);
-extern void __chk_io_ptr(void __iomem *);
+extern void __chk_user_ptr(const void __user *);
+extern void __chk_io_ptr(const void __iomem *);
 #else
 # define __user
 # define __kernel