emulation: qemu-sbsa: Move ITS node into GICv3 node

According to the binding [1] the ITS node should be a subnode of the
GICv3 node. Thus move it now that the driver binds subnodes as well.

1: https://www.kernel.org/doc/Documentation/devicetree/bindings/interrupt-controller/arm%2Cgic-v3.txt

Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>
diff --git a/arch/arm/dts/qemu-sbsa.dts b/arch/arm/dts/qemu-sbsa.dts
index ed00e50..099b51b 100644
--- a/arch/arm/dts/qemu-sbsa.dts
+++ b/arch/arm/dts/qemu-sbsa.dts
@@ -97,11 +97,13 @@
 		      /bits/ 64 <0 0>,
 		      /bits/ 64 <SBSA_GIC_HBASE_ADDR SBSA_GIC_HBASE_LENGTH>,
 		      /bits/ 64 <SBSA_GIC_VBASE_ADDR SBSA_GIC_VBASE_LENGTH>;
-	};
 
-	its {
-		compatible = "arm,gic-v3-its";
-		status = "disabled";
+		its: msi-controller {
+			compatible = "arm,gic-v3-its";
+			msi-controller;
+			#msi-cells = <1>;
+			status = "disabled";
+		};
 	};
 };