ARM: tegra: Add Tegra30 host1x support

Add the host1x node along with its children to the Tegra30 DTSI. Board-
specific DTS files are expected to enable the available outputs and
complement the device tree with data specific to the hardware.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Stephen Warren <swarren@nvidia.com>