ARM: ux500: Add DT node for ux500 PM domains

Add a DT node for the ux500 PM domains. Follow the DT semantics of the
generic PM domain.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

arch/arm/boot/dts/ste-dbx5x0.dtsi

@@ -43,6 +43,10 @@
 			interrupts = <0 7 IRQ_TYPE_LEVEL_HIGH>;
 		};
 
+		pm_domains: pm_domains0 {
+			compatible = "stericsson,ux500-pm-domains";
+			#power-domain-cells = <1>;
+		};
 
 		clocks {
 			compatible = "stericsson,u8500-clks";