powerpc/uaccess: fix warning/error with access_ok()

With the following piece of code, the following compilation warning
is encountered:

	if (_IOC_DIR(ioc) != _IOC_NONE) {
		int verify = _IOC_DIR(ioc) & _IOC_READ ? VERIFY_WRITE : VERIFY_READ;

		if (!access_ok(verify, ioarg, _IOC_SIZE(ioc))) {

drivers/platform/test/dev.c: In function 'my_ioctl':
drivers/platform/test/dev.c:219:7: warning: unused variable 'verify' [-Wunused-variable]
   int verify = _IOC_DIR(ioc) & _IOC_READ ? VERIFY_WRITE : VERIFY_READ;

This patch fixes it by referencing 'type' in the macro allthough
doing nothing with it.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/include/asm/uaccess.h

@@ -63,7 +63,7 @@ static inline int __access_ok(unsigned long addr, unsigned long size,
 #endif
 
 #define access_ok(type, addr, size)		\
-	(__chk_user_ptr(addr),			\
+	(__chk_user_ptr(addr), (void)(type),		\
 	 __access_ok((__force unsigned long)(addr), (size), get_fs()))
 
 /*