arm/tegra: add support for tegra30 based board cardhu

Add support for the tegra30 based cardhu development board. Cardhu is a tablet
formfactor reference design for tegra30. The patch provides a device tree for
the board, updates Makefile.boot to build the dtb, includes the platform in
Kconfig and updates board-dt.c.

Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Colin Cross <ccross@android.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
diff --git a/arch/arm/mach-tegra/board-dt-tegra30.c b/arch/arm/mach-tegra/board-dt-tegra30.c
index f44a29c..3c197e2 100644
--- a/arch/arm/mach-tegra/board-dt-tegra30.c
+++ b/arch/arm/mach-tegra/board-dt-tegra30.c
@@ -47,6 +47,7 @@
 }
 
 static const char *tegra30_dt_board_compat[] = {
+	"nvidia,cardhu",
 	NULL
 };