extcon: max77693: add device-tree compatible string

Commit 57f706bf7307 ("ARM: dts: samsung: exynos4412-midas: add USB
connector and USB OTG") added a 'muic' node to the MAX77693 PMIC
definition in various device-tree files. Since that commit, the newly
created MFD cell gained its own of_node and compatible string. This
changed its modalias, what in turn broke automated loading of the driver
module, because the new modalias is based on the of_node compatible
string, not the platform device name.

Fix this by adding the needed device-tree compatible string.

Link: https://lore.kernel.org/all/[e-mail]/
Signed-off-by: Marek Szyprowski <[e-mail]>
Reviewed-by: Krzysztof Kozlowski <[e-mail]>
Signed-off-by: Chanwoo Choi <[e-mail]>

drivers/extcon/extcon-max77693.c

···
 	return ret;
 }
 
+static const struct of_device_id of_max77693_muic_dt_match[] = {
+	{ .compatible = "maxim,max77693-muic", },
+	{ /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, of_max77693_muic_dt_match);
+
 static struct platform_driver max77693_muic_driver = {
 	.driver		= {
 		.name	= DEV_NAME,
+		.of_match_table = of_max77693_muic_dt_match,
 	},
 	.probe		= max77693_muic_probe,
 };