[E81][B79][DTB] Add device trees for E81 on B79 with dual-LVDS display

This was too easy...

arch/arm64/boot/dts/seco/include/baseboard-e81-b79.dtsi

@@ -85,6 +85,16 @@ reg_3v3_aud: 3v3_aud {
 		regulator-always-on;
 	};
 
+	reg_3v3_sdcard: reg_3v3_sdcard {
+		compatible = "regulator-fixed";
+		regulator-name = "3.3V_SDCARD";
+		vin-supply = <&reg_3v3_a>;
+		regulator-min-microvolt = <3300000>;
+		regulator-max-microvolt = <3300000>;
+		gpio = <&stm32 21 GPIO_ACTIVE_HIGH>;
+		regulator-always-on;
+		enable-active-high;
+	};
 };
 
 &stm32 {
@@ -145,4 +155,8 @@ eeprom: eeprom@57 {
 	};
 };
 
+&sdhc_2 {
+	status = "okay";
+};
+
 #endif