[media] tc358743: make reset gpio optional

Commit 2561482468 ("[media] tc358743: support probe from device tree")
specified in the device tree binding documentation that the reset gpio
is optional. Make the implementation match accordingly.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

drivers/media/i2c/tc358743.c

@@ -1782,14 +1782,16 @@ static int tc358743_probe_of(struct tc358743_state *state)
 	state->pdata.ths_trailcnt = 0x2;
 	state->pdata.hstxvregcnt = 0;
 
-	state->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
+	state->reset_gpio = devm_gpiod_get_optional(dev, "reset",
+						    GPIOD_OUT_LOW);
 	if (IS_ERR(state->reset_gpio)) {
 		dev_err(dev, "failed to get reset gpio\n");
 		ret = PTR_ERR(state->reset_gpio);
 		goto disable_clk;
 	}
 
-	tc358743_gpio_reset(state);
+	if (state->reset_gpio)
+		tc358743_gpio_reset(state);
 
 	ret = 0;
 	goto free_endpoint;