ARM: dts: Use simple-pm-bus for genpd for am4 l4_fast

We can now enable simple-pm-bus to use genpd.

Signed-off-by: Tony Lindgren <[e-mail]>

arch/arm/boot/dts/am437x-l4.dtsi

···
 };
 
 &l4_fast {					/* 0x4a000000 */
-	compatible = "ti,am4-l4-fast", "simple-bus";
+	compatible = "ti,am4-l4-fast", "simple-pm-bus";
+	power-domains = <&prm_per>;
+	clocks = <&l3_clkctrl AM4_L3_L4_HS_CLKCTRL 0>;
+	clock-names = "fck";
 	reg = <0x4a000000 0x800>,
 	      <0x4a000800 0x800>,
 	      <0x4a001000 0x400>;
···
 	ranges = <0x00000000 0x4a000000 0x1000000>;	/* segment 0 */
 
 	segment@0 {					/* 0x4a000000 */
-		compatible = "simple-bus";
+		compatible = "simple-pm-bus";
 		#address-cells = <1>;
 		#size-cells = <1>;
 		ranges = <0x00000000 0x00000000 0x000800>,	/* ap 0 */