Input: cyapa - do not set otherwise unused variable

As the name suggests, always_unused argument in cyapa_gen3_set_power_mode()
is never used, so there is no reason for setting it to 0.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/mouse/cyapa_gen3.c

@@ -957,7 +957,6 @@ static int cyapa_gen3_set_power_mode(struct cyapa *cyapa, u8 power_mode,
 	int tries;
 	u16 sleep_time;
 
-	always_unused = 0;
 	if (cyapa->state != CYAPA_STATE_OP)
 		return 0;