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/drivers/i2c/Kconfig b/drivers/i2c/Kconfig
index e42b651..f8b18de 100644
--- a/drivers/i2c/Kconfig
+++ b/drivers/i2c/Kconfig
@@ -402,7 +402,7 @@
 
 config SYS_I2C_TEGRA
 	bool "NVIDIA Tegra internal I2C controller"
-	depends on TEGRA
+	depends on ARCH_TEGRA
 	help
 	  Support for NVIDIA I2C controller available in Tegra SoCs.