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/cpu/armv7/Kconfig b/arch/arm/cpu/armv7/Kconfig
index 73d57a2..14569e5 100644
--- a/arch/arm/cpu/armv7/Kconfig
+++ b/arch/arm/cpu/armv7/Kconfig
@@ -19,7 +19,7 @@
 config ARMV7_BOOT_SEC_DEFAULT
 	bool "Boot in secure mode by default" if EXPERT
 	depends on ARMV7_NONSEC
-	default y if TEGRA
+	default y if ARCH_TEGRA
 	---help---
 	Say Y here to boot in secure mode by default even if non-secure mode
 	is supported. This option is useful to boot kernels which do not