ARM: tegra: convert CONFIG_TEGRA_GPIO to Kconfig

Future chips will contain different GPIO HW. This change will enable
future SoC support to select the appropriate GPIO driver for their HW,
in a future-looking fashion, using Kconfig.

TEGRA_GPIO is not simply selected by TEGRA_COMMON (even though all
current Tegra chips used this GPIO HW) to simplify the later addition
of support for Tegra SoCs that use different GPIO HW.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Warren <twarren@nvidia.com>
diff --git a/arch/arm/mach-tegra/Kconfig b/arch/arm/mach-tegra/Kconfig
index ba6983f..616a1c3 100644
--- a/arch/arm/mach-tegra/Kconfig
+++ b/arch/arm/mach-tegra/Kconfig
@@ -22,6 +22,7 @@
 	select SPL
 	select SUPPORT_SPL
 	select TEGRA_COMMON
+	select TEGRA_GPIO
 
 config TEGRA_ARMV8_COMMON
 	bool "Tegra 64-bit common options"
@@ -50,6 +51,7 @@
 
 config TEGRA210
 	bool "Tegra210 family"
+	select TEGRA_GPIO
 	select TEGRA_ARMV8_COMMON
 
 endchoice