parisc: Avoid compiler warnings with access_ok()

Commit 09b871ffd4 (parisc: Define access_ok() as macro) missed to mark uaddr
as used, which then gives compiler warnings about unused variables.

Fix it by comparing uaddr to uaddr which then gets optimized away by the
compiler.

Signed-off-by: Helge Deller <deller@gmx.de>
Fixes: 09b871ffd4 ("parisc: Define access_ok() as macro")

arch/parisc/include/asm/uaccess.h

@@ -32,7 +32,8 @@
  * that put_user is the same as __put_user, etc.
  */
 
-#define access_ok(type, uaddr, size) (1)
+#define access_ok(type, uaddr, size)	\
+	( (uaddr) == (uaddr) )
 
 #define put_user __put_user
 #define get_user __get_user