ARM: dts: Configure power-domain for omap4 gfx

Configure power-domain for omap4 dts gfx in preparation to
probing devices with simple-pm-bus and genpd.

Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/boot/dts/omap4.dtsi

@@ -440,6 +440,7 @@
 					<SYSC_IDLE_NO>,
 					<SYSC_IDLE_SMART>,
 					<SYSC_IDLE_SMART_WKUP>;
+			power-domains = <&prm_gfx>;
 			clocks = <&l3_gfx_clkctrl OMAP4_GPU_CLKCTRL 0>;
 			clock-names = "fck";
 			#address-cells = <1>;