arm64: dts: qcom: sm6125: Avoid using missing SM6125_VDDCX

The SM6125_VDDCX constant is introduced through a separate branch and is
not available in the dts branch. Temporarily replace the constant with
it's value to avoid the build breakage.
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

arch/arm64/boot/dts/qcom/sm6125.dtsi

@@ -449,7 +449,7 @@ sdhc_1: sdhci@4744000 {
 				 <&xo_board>;
 			clock-names = "iface", "core", "xo";
 
-			power-domains = <&rpmpd SM6125_VDDCX>;
+			power-domains = <&rpmpd 0>;
 
 			bus-width = <8>;
 			non-removable;
@@ -474,7 +474,7 @@ sdhc_2: sdhci@4784000 {
 			pinctrl-1 = <&sdc2_state_off>;
 			pinctrl-names = "default", "sleep";
 
-			power-domains = <&rpmpd SM6125_VDDCX>;
+			power-domains = <&rpmpd 0>;
 
 			bus-width = <4>;
 			status = "disabled";