[media] serio.h: add SERIO_RAINSHADOW_CEC ID

Add a new serio ID for the RainShadow Tech USB HDMI CEC adapter.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

include/uapi/linux/serio.h

@@ -80,5 +80,6 @@
 #define SERIO_WACOM_IV	0x3e
 #define SERIO_EGALAX	0x3f
 #define SERIO_PULSE8_CEC	0x40
+#define SERIO_RAINSHADOW_CEC	0x41
 
 #endif /* _UAPI_SERIO_H */