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/tegra30.dtsi b/arch/arm/boot/dts/tegra30.dtsi
index 15200a9..9d650fb 100644
--- a/arch/arm/boot/dts/tegra30.dtsi
+++ b/arch/arm/boot/dts/tegra30.dtsi
@@ -224,4 +224,9 @@
 			nvidia,ahub-cif-ids = <8 8>;
 		};
 	};
+
+	ahb: ahb@6000c004 {
+		compatible = "nvidia,tegra30-ahb";
+		reg = <0x6000c004 0x14c>; /* AHB Arbitration + Gizmo Controller */
+	};
 };