arm64: tegra: Enable IOMMU for host1x on Tegra210

The host1x driver now supports operation behind an IOMMU, so add its
IOMMU domain to the device tree.
Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

arch/arm64/boot/dts/nvidia/tegra210.dtsi

@@ -89,6 +89,8 @@ host1x@50000000 {
 
 		ranges = <0x0 0x54000000 0x0 0x54000000 0x0 0x01000000>;
 
+		iommus = <&mc TEGRA_SWGROUP_HC>;
+
 		dpaux1: dpaux@54040000 {
 			compatible = "nvidia,tegra210-dpaux";
 			reg = <0x0 0x54040000 0x0 0x00040000>;