riscv: dts: starfive: Unify regulator naming scheme

Currently, there are 3 regulators defined in JH7110's common device tree,
but regulator names are mixed with "-" and "_". So unify them to "_",
which is more often to be seen in other dts files.

Signed-off-by: Shengyu Qu <wiagn233@outlook.com>
Acked-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>

Author: Headcrabed

arch/riscv/boot/dts/starfive/jh7110-common.dtsi

@@ -233,7 +233,7 @@
 				regulator-always-on;
 				regulator-min-microvolt = <500000>;
 				regulator-max-microvolt = <1540000>;
-				regulator-name = "vdd-cpu";
+				regulator-name = "vdd_cpu";
 			};
 
 			emmc_vdd: aldo4 {