ARM: ux500: Add Device Tree nodes for AB8500 External regulators

The AB8500 has 3 external regulators which are used to control outside
voltage sources. Some of the core AB8500 use these external regulators
as a supply, so they must be obtainable via Device Tree.
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

arch/arm/boot/dts/dbx5x0.dtsi

@@ -457,6 +457,33 @@ codec: ab8500-codec {
 					stericsson,earpeice-cmv = <950>; /* Units in mV. */
 				};
 
+				ext_regulators: ab8500-ext-regulators {
+					compatible = "stericsson,ab8500-ext-regulator";
+
+					ab8500_ext1_reg: ab8500_ext1 {
+						regulator-compatible = "ab8500_ext1";
+						regulator-min-microvolt = <1800000>;
+						regulator-max-microvolt = <1800000>;
+						regulator-boot-on;
+						regulator-always-on;
+					};
+
+					ab8500_ext2_reg: ab8500_ext2 {
+						regulator-compatible = "ab8500_ext2";
+						regulator-min-microvolt = <1360000>;
+						regulator-max-microvolt = <1360000>;
+						regulator-boot-on;
+						regulator-always-on;
+					};
+
+					ab8500_ext3_reg: ab8500_ext3 {
+						regulator-compatible = "ab8500_ext3";
+						regulator-min-microvolt = <3400000>;
+						regulator-max-microvolt = <3400000>;
+						regulator-boot-on;
+					};
+				};
+
 				ab8500-regulators {
 					compatible = "stericsson,ab8500-regulator";