ARM: tegra: Hide EMC scaling config behind ARCH_TEGRA

The option isn't terribly useful on other ARM platforms.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Colin Cross <ccross@android.com>

arch/arm/mach-tegra/Kconfig

@@ -64,7 +64,7 @@ config TEGRA_SYSTEM_DMA
 	  Adds system DMA functionality for NVIDIA Tegra SoCs, used by
 	  several Tegra device drivers
 
-endif
-
 config TEGRA_EMC_SCALING_ENABLE
 	bool "Enable scaling the memory frequency"
+
+endif