arm64: tegra: Enable SMMU for XUSB host on Tegra186

Enabling the SMMU for XUSB host allows buffers to be mapped through the
ARM SMMU, which helps protecting the system from rogue memory accesses
by the XUSB host.
Signed-off-by: Nagarjuna Kristam <nkristam@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

arch/arm64/boot/dts/nvidia/tegra186.dtsi

@@ -525,6 +525,7 @@ usb@3530000 {
 		      <0x0 0x03538000 0x0 0x1000>;
 		reg-names = "hcd", "fpci";
 
+		iommus = <&smmu TEGRA186_SID_XUSB_HOST>;
 		interrupts = <GIC_SPI 163 IRQ_TYPE_LEVEL_HIGH>,
 			     <GIC_SPI 164 IRQ_TYPE_LEVEL_HIGH>,
 			     <GIC_SPI 167 IRQ_TYPE_LEVEL_HIGH>;