Convert CONFIG_SPL_LIBCOMMON_SUPPORT to Kconfig

Move this option to Kconfig and tidy up existing uses.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/arm/mach-tegra/Kconfig b/arch/arm/mach-tegra/Kconfig
index 6b1cedf..ce48d25 100644
--- a/arch/arm/mach-tegra/Kconfig
+++ b/arch/arm/mach-tegra/Kconfig
@@ -3,6 +3,9 @@
 config SPL_GPIO_SUPPORT
 	default y
 
+config SPL_LIBCOMMON_SUPPORT
+	default y
+
 config TEGRA_IVC
 	bool "Tegra IVC protocol"
 	help