mfd: mt6397-core: Add GPIO sub-module support

Signed-off-by: Hongzhou Yang <hongzhou.yang@mediatek.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
diff --git a/drivers/mfd/mt6397-core.c b/drivers/mfd/mt6397-core.c
index 32775eb..38a0458 100644
--- a/drivers/mfd/mt6397-core.c
+++ b/drivers/mfd/mt6397-core.c
@@ -34,6 +34,9 @@
 	}, {
 		.name = "mt6397-clk",
 		.of_compatible = "mediatek,mt6397-clk",
+	}, {
+		.name = "mt6397-pinctrl",
+		.of_compatible = "mediatek,mt6397-pinctrl",
 	},
 };