ASoC: rt5645: Fix potential crash in jd function

If no one defined the rt5645->pdata.hp_det_gpio in coreboot/bios.
It will cause kernel to reboot because rt5645->pdata.hp_det_gpio
is 0. So it is worth to add a check in rt5645_jack_detect.

Signed-off-by: Bard Liao <bardliao@realtek.com>
Signed-off-by: Fang, Yang A <yang.a.fang@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/sound/soc/codecs/rt5645.c b/sound/soc/codecs/rt5645.c
index d16331e..c901ef6 100644
--- a/sound/soc/codecs/rt5645.c
+++ b/sound/soc/codecs/rt5645.c
@@ -2113,6 +2113,10 @@
 	int gpio_state, jack_type = 0;
 	unsigned int val;
 
+	if (!gpio_is_valid(rt5645->pdata.hp_det_gpio)) {
+		dev_err(codec->dev, "invalid gpio\n");
+		return -EINVAL;
+	}
 	gpio_state = gpio_get_value(rt5645->pdata.hp_det_gpio);
 
 	dev_dbg(codec->dev, "gpio = %d(%d)\n", rt5645->pdata.hp_det_gpio,