arm64: dts: imx8mq-librem5: Don't mark buck3 as always on

With the pmic driver fixed we can now shut off the regulator in the gpc.
Signed-off-by: NGuido Günther <agx@sigxcpu.org>
Signed-off-by: NMartin Kepplinger <martin.kepplinger@puri.sm>
Signed-off-by: NShawn Guo <shawnguo@kernel.org>

arch/arm64/boot/dts/freescale/imx8mq-librem5.dtsi

@@ -679,7 +679,6 @@
 				regulator-min-microvolt = <700000>;
 				regulator-max-microvolt = <1300000>;
 				rohm,dvs-run-voltage = <900000>;
-				regulator-always-on;
 			};
 
 			buck4_reg: BUCK4 {