denver: modify wl2864c driver

[detail]
use gpiod to eanble gpio, fix build error in Android R.

Change-Id: I6ebf639b2f90ab1c66d1d7b4e5d78d2c85a09d37
Signed-off-by: liuwang2 <liuwang2@lenovo.com>
Reviewed-on: https://gerrit.mot.com/1763843
SLTApproved: Slta Waiver
SME-Granted: SME Approvals Granted
Tested-by: Jira Key
Reviewed-by: Dawei Wang <wangdw10@motorola.com>
Reviewed-by: Zhenxin Xi <xizx@motorola.com>
Reviewed-by: Long Cheng <chengl1@motorola.com>
Submit-Approved: Jira Key

drivers/regulator/wl2864c/wl2864c-regulator.c

@@ -131,8 +131,8 @@ static int wl2864c_of_parse_cb(struct device_node *np,
 	int ena_gpio;
 
 	ena_gpio = of_get_named_gpio(np, "enable-gpios", 0);
-	if (ena_gpio)
-		config->ena_gpio = ena_gpio;
+	if (gpio_is_valid(ena_gpio))
+		config->ena_gpiod = gpio_to_desc(ena_gpio);
 
 	return 0;
 }