arm64: dts: qcom: sc7280: add simple-mfd to IMEM

The IMEM node has children (PIL) which should be instantiated with
simple-mfd.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220607171848.535128-11-krzysztof.kozlowski@linaro.org

arch/arm64/boot/dts/qcom/sc7280.dtsi

@@ -4767,7 +4767,7 @@ sdc2_data_sleep: sdc2-data-sleep {
 		};
 
 		sram@146a5000 {
-			compatible = "qcom,sc7280-imem", "syscon";
+			compatible = "qcom,sc7280-imem", "syscon", "simple-mfd";
 			reg = <0 0x146a5000 0 0x6000>;
 
 			#address-cells = <1>;