pinctrl: mediatek: add driver for MT7622

This patch add Pinctrl driver for MediaTek MT7622 SoC.

diff --git a/drivers/pinctrl/mediatek/Kconfig b/drivers/pinctrl/mediatek/Kconfig
index 9c6b580..58df508 100644
--- a/drivers/pinctrl/mediatek/Kconfig
+++ b/drivers/pinctrl/mediatek/Kconfig
@@ -4,6 +4,10 @@
 	depends on PINCTRL_GENERIC
 	bool
 
+config PINCTRL_MT7622
+	bool "MT7622 SoC pinctrl driver"
+	select PINCTRL_MTK
+
 config PINCTRL_MT7623
 	bool "MT7623 SoC pinctrl driver"
 	select PINCTRL_MTK