ARM: dt: tegra: Add device tree support for AHB

Add AHB entry for tegra20/30.

Signed-off-by: Hiroshi DOYU <hdoyu@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
diff --git a/arch/arm/boot/dts/tegra20.dtsi b/arch/arm/boot/dts/tegra20.dtsi
index 108e894..24129fb 100644
--- a/arch/arm/boot/dts/tegra20.dtsi
+++ b/arch/arm/boot/dts/tegra20.dtsi
@@ -206,5 +206,10 @@
 		interrupts = < 0 97 0x04 >;
 		phy_type = "utmi";
 	};
+
+	ahb: ahb@6000c004 {
+		compatible = "nvidia,tegra20-ahb";
+		reg = <0x6000c004 0x10c>; /* AHB Arbitration + Gizmo Controller */
+	};
 };