[media] ir-raw: fix sparse non-ANSI function warning

Fix sparse warning for non-ANSI function declaration:

drivers/media/rc/ir-raw.c:247:30: warning: non-ANSI function declaration of function 'ir_raw_get_allowed_protocols'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc:	Mauro Carvalho Chehab <mchehab@infradead.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/rc/ir-raw.c

@@ -233,7 +233,7 @@ EXPORT_SYMBOL_GPL(ir_raw_event_handle);
 
 /* used internally by the sysfs interface */
 u64
-ir_raw_get_allowed_protocols()
+ir_raw_get_allowed_protocols(void)
 {
 	u64 protocols;
 	mutex_lock(&ir_raw_handler_lock);