[media] rc-core: lirc use unsigned int

Durations can never be negative, so it makes sense to consistently use
unsigned int for LIRC transmission. Contrary to the initial impression,
this shouldn't actually change the userspace API.

Signed-off-by: David Härdeman <david@hardeman.nu>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/include/media/rc-core.h b/include/media/rc-core.h
index 60536c7..b1f19b7 100644
--- a/include/media/rc-core.h
+++ b/include/media/rc-core.h
@@ -117,7 +117,7 @@
 	int				(*s_tx_carrier)(struct rc_dev *dev, u32 carrier);
 	int				(*s_tx_duty_cycle)(struct rc_dev *dev, u32 duty_cycle);
 	int				(*s_rx_carrier_range)(struct rc_dev *dev, u32 min, u32 max);
-	int				(*tx_ir)(struct rc_dev *dev, int *txbuf, u32 n);
+	int				(*tx_ir)(struct rc_dev *dev, unsigned *txbuf, unsigned n);
 	void				(*s_idle)(struct rc_dev *dev, bool enable);
 	int				(*s_learning_mode)(struct rc_dev *dev, int enable);
 	int				(*s_carrier_report) (struct rc_dev *dev, int enable);