rename symbol: CONFIG_TEGRA -> CONFIG_ARCH_TEGRA

Have this symbol follow the pattern of all other such symbols.

Signed-off-by: Trevor Woerner <twoerner@gmail.com>
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 8bdcf34..6152b11 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1142,7 +1142,7 @@
 	imply MP
 	imply DM_USB_GADGET
 
-config TEGRA
+config ARCH_TEGRA
 	bool "NVIDIA Tegra"
 	imply DISTRO_DEFAULTS
 	imply FAT_WRITE