backlight: pwm_bl: Remove unneeded checks for valid GPIOs

All of gpiod_set_value_cansleep() and gpiod_direction_output() handle
NULL GPIO pointers just fine, so there is no need to check for that in
the caller.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/00be8237e0e2bc9b179177b5490f175d657261a2.1684856337.git.geert+renesas@glider.beSigned-off-by: Lee Jones <lee@kernel.org>

drivers/video/backlight/pwm_bl.c

@@ -54,8 +54,7 @@ static void pwm_backlight_power_on(struct pwm_bl_data *pb)
 	if (pb->post_pwm_on_delay)
 		msleep(pb->post_pwm_on_delay);
 
-	if (pb->enable_gpio)
-		gpiod_set_value_cansleep(pb->enable_gpio, 1);
+	gpiod_set_value_cansleep(pb->enable_gpio, 1);
 
 	pb->enabled = true;
 }
@@ -65,8 +64,7 @@ static void pwm_backlight_power_off(struct pwm_bl_data *pb)
 	if (!pb->enabled)
 		return;
 
-	if (pb->enable_gpio)
-		gpiod_set_value_cansleep(pb->enable_gpio, 0);
+	gpiod_set_value_cansleep(pb->enable_gpio, 0);
 
 	if (pb->pwm_off_delay)
 		msleep(pb->pwm_off_delay);
@@ -429,8 +427,7 @@ static int pwm_backlight_initial_power_state(const struct pwm_bl_data *pb)
 	 * Synchronize the enable_gpio with the observed state of the
 	 * hardware.
 	 */
-	if (pb->enable_gpio)
-		gpiod_direction_output(pb->enable_gpio, active);
+	gpiod_direction_output(pb->enable_gpio, active);
 
 	/*
 	 * Do not change pb->enabled here! pb->enabled essentially