arm64: dts: qcom: ipq6018: add LDOA2 regulator

Add LDOA2 regulator from MP5496 to support SDCC voltage scaling.

Suggested-by: Robert Marko <robimarko@gmail.com>
Signed-off-by: Chukun Pan <amadeus@jmu.edu.cn>
Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20250210070122.208842-6-amadeus@jmu.edu.cn
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

arch/arm64/boot/dts/qcom/ipq6018-mp5496.dtsi

@@ -31,5 +31,14 @@
 			regulator-max-microvolt = <1062500>;
 			regulator-always-on;
 		};
+
+		mp5496_l2: l2 {
+			regulator-min-microvolt = <1800000>;
+			regulator-max-microvolt = <3300000>;
+		};
 	};
 };
+
+&sdhc {
+	vqmmc-supply = <&mp5496_l2>;
+};