soc/tegra: Provide per-SoC Kconfig symbols

Move per-SoC generation Kconfig symbols to drivers/soc/tegra/Kconfig to
gather them all in a single place. This directory is a natural location
for these options since it already contains the drivers that are shared
across 32-bit and 64-bit ARM architectures.

Signed-off-by: Thierry Reding <treding@nvidia.com>
diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig
index 4e853ed..a8d72ba 100644
--- a/drivers/soc/Kconfig
+++ b/drivers/soc/Kconfig
@@ -5,6 +5,7 @@
 source "drivers/soc/qcom/Kconfig"
 source "drivers/soc/rockchip/Kconfig"
 source "drivers/soc/sunxi/Kconfig"
+source "drivers/soc/tegra/Kconfig"
 source "drivers/soc/ti/Kconfig"
 source "drivers/soc/versatile/Kconfig"