ARM: dts: am3517-evm: Remove unnessary PMIC parameters

The AM3517-EVM uses a TPS65023 PMIC.  This is already defined
by:  compatible = "ti,tps65023"

There doesn't seem to be a need to have each regulator in the
PMIC with the 'compatible = "regulator-fixed"' since each
regulator has a min and max setting.
Signed-off-by: Adam Ford <aford173@gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/boot/dts/am3517-som.dtsi

@@ -64,7 +64,6 @@ tps: tps65023@48 {
 		regulators {
 			vdd_core_reg: VDCDC1 {
 				regulator-name = "vdd_core";
-				compatible = "regulator-fixed";
 				regulator-always-on;
 				regulator-min-microvolt = <1200000>;
 				regulator-max-microvolt = <1200000>;
@@ -72,7 +71,6 @@ vdd_core_reg: VDCDC1 {
 
 			vdd_io_reg: VDCDC2 {
 				regulator-name = "vdd_io";
-				compatible = "regulator-fixed";
 				regulator-always-on;
 				regulator-min-microvolt = <3300000>;
 				regulator-max-microvolt = <3300000>;
@@ -80,7 +78,6 @@ vdd_io_reg: VDCDC2 {
 
 			vdd_1v8_reg: VDCDC3 {
 				regulator-name = "vdd_1v8";
-				compatible = "regulator-fixed";
 				regulator-always-on;
 				regulator-min-microvolt = <1800000>;
 				regulator-max-microvolt = <1800000>;
@@ -88,7 +85,6 @@ vdd_1v8_reg: VDCDC3 {
 
 			vdd_usb18_reg: LDO1 {
 				regulator-name = "vdd_usb18";
-				compatible = "regulator-fixed";
 				regulator-always-on;
 				regulator-min-microvolt = <1800000>;
 				regulator-max-microvolt = <1800000>;
@@ -96,7 +92,6 @@ vdd_usb18_reg: LDO1 {
 
 			vdd_usb33_reg: LDO2 {
 				regulator-name = "vdd_usb33";
-				compatible = "regulator-fixed";
 				regulator-always-on;
 				regulator-min-microvolt = <3300000>;
 				regulator-max-microvolt = <3300000>;