drm: Add NVIDIA Tegra20 support

This commit adds a KMS driver for the Tegra20 SoC. This includes basic
support for host1x and the two display controllers found on the Tegra20
SoC. Each display controller can drive a separate RGB/LVDS output.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Tested-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Mark Zhang <markz@nvidia.com>
Reviewed-by: Mark Zhang <markz@nvidia.com>
Tested-by: Mark Zhang <markz@nvidia.com>
Tested-and-acked-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-by: Terje Bergstrom <tbergstrom@nvidia.com>
Tested-by: Terje Bergstrom <tbergstrom@nvidia.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
index 18321b68b..983201b 100644
--- a/drivers/gpu/drm/Kconfig
+++ b/drivers/gpu/drm/Kconfig
@@ -210,3 +210,5 @@
 source "drivers/gpu/drm/cirrus/Kconfig"
 
 source "drivers/gpu/drm/shmobile/Kconfig"
+
+source "drivers/gpu/drm/tegra/Kconfig"