pinctrl: exynos: Add pinctrl support for Exynos850

Add pinctrl support for Exynos850 SoC. It was mostly extracted from
corresponding Linux kernel code [1]. Power down modes and external
interrupt data were removed while converting the code for U-Boot, but
everything else was kept almost unchanged.

[1] drivers/pinctrl/samsung/pinctrl-exynos-arm64.c

Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
Reviewed-by: Chanho Park <chanho61.park@samsung.com>
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
diff --git a/drivers/pinctrl/exynos/Kconfig b/drivers/pinctrl/exynos/Kconfig
index a60f498..1b7fb62 100644
--- a/drivers/pinctrl/exynos/Kconfig
+++ b/drivers/pinctrl/exynos/Kconfig
@@ -16,3 +16,11 @@
 	help
 	  Support pin multiplexing and pin configuration control on
 	  Samsung's Exynos78x0 SoC.
+
+config PINCTRL_EXYNOS850
+	bool "Samsung Exynos850 pinctrl driver"
+	depends on ARCH_EXYNOS && PINCTRL_FULL
+	select PINCTRL_EXYNOS
+	help
+	  Support pin multiplexing and pin configuration control on
+	  Samsung's Exynos850 SoC.