ARM: tegra: colibri_t20: use high speed uart driver

Use high speed UART driver compatible nvidia,tegra20-hsuart.
Signed-off-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

arch/arm/boot/dts/tegra20-colibri.dtsi

@@ -423,6 +423,14 @@ ac97: ac97@70002000 {
 			<&gpio TEGRA_GPIO(P, 0) GPIO_ACTIVE_HIGH>;
 	};
 
+	serial@70006040 {
+		compatible = "nvidia,tegra20-hsuart";
+	};
+
+	serial@70006300 {
+		compatible = "nvidia,tegra20-hsuart";
+	};
+
 	nand-controller@70008000 {
 		status = "okay";