openrisc: uaccess: Add user address space check to access_ok

Now that __user annotations are fixed for openrisc uaccess api's we can
add checking to the access_ok macro.  This patch adds the __chk_user_ptr
check, on normal builds the added check is a nop.

Signed-off-by: Stafford Horne <shorne@gmail.com>
Reviewed-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>

arch/openrisc/include/asm/uaccess.h

@@ -57,6 +57,7 @@ static inline int __range_ok(unsigned long addr, unsigned long size)
 
 #define access_ok(addr, size)						\
 ({ 									\
+	__chk_user_ptr(addr);						\
 	__range_ok((unsigned long)(addr), (size));			\
 })