arm64: tegra: Add XUSB pad controller's "nvidia,pmc" property on Tegra210

PMC driver provides USB sleepwalk registers access to XUSB PADCTL
driver. This commit adds a "nvidia,pmc" property which points to
PMC node to XUSB PADCTL device node.
Signed-off-by: JC Kuo <jckuo@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

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

@@ -1044,6 +1044,7 @@ padctl: padctl@7009f000 {
 		interrupts = <GIC_SPI 49 IRQ_TYPE_LEVEL_HIGH>;
 		resets = <&tegra_car 142>;
 		reset-names = "padctl";
+		nvidia,pmc =  <&tegra_pmc>;
 
 		status = "disabled";