arm64: dts: ti: k3-j7200: Make the FSS node a simple-bus

To do this we convert hbmc-mux to "reg-mux", then the FSS node
does not need to be a syscon, so change to "simple-bus". This
removes a DTS check warning.
Signed-off-by: Andrew Davis <afd@ti.com>
Link: https://lore.kernel.org/r/20240124184722.150615-9-afd@ti.comSigned-off-by: Vignesh Raghavendra <vigneshr@ti.com>

arch/arm64/boot/dts/ti/k3-j7200-mcu-wakeup.dtsi

@@ -518,17 +518,18 @@ mcu_spi2: spi@40320000 {
 		status = "disabled";
 	};
 
-	fss: syscon@47000000 {
-		compatible = "syscon", "simple-mfd";
+	fss: bus@47000000 {
+		compatible = "simple-bus";
 		reg = <0x00 0x47000000 0x00 0x100>;
 		#address-cells = <2>;
 		#size-cells = <2>;
 		ranges;
 
-		hbmc_mux: hbmc-mux {
-			compatible = "mmio-mux";
+		hbmc_mux: mux-controller@47000004 {
+			compatible = "reg-mux";
+			reg = <0x00 0x47000004 0x00 0x4>;
 			#mux-control-cells = <1>;
-			mux-reg-masks = <0x4 0x2>; /* HBMC select */
+			mux-reg-masks = <0x0 0x2>; /* HBMC select */
 		};
 
 		hbmc: hyperbus@47034000 {