regulator: bcm590xx: Fix .enable_reg for BCM590XX_REG_VSR

Current implementation missed the case BCM590XX_REG_VSR, so
bcm590xx_get_enable_register() returns 0 when id is BCM590XX_REG_VSR.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers/regulator/bcm590xx-regulator.c

@@ -242,8 +242,12 @@ static int bcm590xx_get_enable_register(int id)
 		case BCM590XX_REG_SDSR2:
 			reg = BCM590XX_SDSR2PMCTRL1;
 			break;
+		case BCM590XX_REG_VSR:
+			reg = BCM590XX_VSRPMCTRL1;
+			break;
 		case BCM590XX_REG_VBUS:
 			reg = BCM590XX_OTG_CTRL;
+			break;
 		}