[media] saa7134.h: Suppress compiler warnings when CONFIG_VIDEO_SAA7134_RC is not set

If the said config optio is not set, the compiler will spill out many
warnings about statements with no effect, such as:

Casting the zero to void will cure the warning.
Signed-off-by: Timo Kokkonen <kaapeli@itanic.dy.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/saa7134/saa7134.h

@@ -843,10 +843,10 @@ void saa7134_probe_i2c_ir(struct saa7134_dev *dev);
 int saa7134_ir_start(struct saa7134_dev *dev);
 void saa7134_ir_stop(struct saa7134_dev *dev);
 #else
-#define saa7134_input_init1(dev)	(0)
-#define saa7134_input_fini(dev)		(0)
-#define saa7134_input_irq(dev)		(0)
-#define saa7134_probe_i2c_ir(dev)	(0)
-#define saa7134_ir_start(dev)		(0)
-#define saa7134_ir_stop(dev)		(0)
+#define saa7134_input_init1(dev)	((void)0)
+#define saa7134_input_fini(dev)		((void)0)
+#define saa7134_input_irq(dev)		((void)0)
+#define saa7134_probe_i2c_ir(dev)	((void)0)
+#define saa7134_ir_start(dev)		((void)0)
+#define saa7134_ir_stop(dev)		((void)0)
 #endif