arm64: tegra: Mark I2C4 as DDC on P3310

The P3310 compute module assigns the I2C4 to be used for DDC operations.
Signed-off-by: Thierry Reding <treding@nvidia.com>

arch/arm64/boot/dts/nvidia/tegra186-p3310.dtsi

@@ -77,7 +77,7 @@ i2c@3180000 {
 		status = "okay";
 	};
 
-	i2c@3190000 {
+	ddc: i2c@3190000 {
 		status = "okay";
 	};