arm64: tegra: Enable PWM on Jetson Nano

Signed-off-by: Thierry Reding <treding@nvidia.com>

arch/arm64/boot/dts/nvidia/tegra210-p3450-0000.dts

@@ -88,6 +88,10 @@ serial@70006000 {
 		status = "okay";
 	};
 
+	pwm@7000a000 {
+		status = "okay";
+	};
+
 	i2c@7000c500 {
 		status = "okay";
 		clock-frequency = <100000>;