Revert "power: regulator: Add vin-supply for GPIO and Fixed regulators"

Rockchip boards may depend on a working MMC regulator in SPL to
successfully load FIT payload from MMC. Typically, these boards only
include the vmmc-supply regulator and not its vin-supply in SPL control
FDT.

The commit f98d812e53 ("power: regulator: Add vin-supply for GPIO and
Fixed regulators") breaks loading FIT from MMC in SPL on some of these
boards due to now requiring the vin-supply to be included in the SPL
control FDT.

The commit also strangely enables any found vin-supply in
regulator_common_of_to_plat() and not when a regulator is enabled or as
part of regulator_autoset().

Revert the commit to fix FIT loading in SPL on broken boards.

If a board needs to have its vin-supply enabled, two options come to
mind:

- Add regulator-always-on prop to the regulator in the -u-boot.dtsi for
  any board.

- Implement full support for reference counting of regulators and then
  update the regulator-uclass to enable any found vin-supply when a
  regulator is enabled.

This reverts commit f98d812e53.

Reported-by: Dang Huynh <danct12@riseup.net>
Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Reviewed-by: Dragan Simic <dsimic@manjaro.org>

drivers/power/regulator/regulator_common.c

@@ -44,16 +44,6 @@ int regulator_common_of_to_plat(struct udevice *dev,
 			dev_read_u32_default(dev, "u-boot,off-on-delay-us", 0);
 	}
 
-	ret = device_get_supply_regulator(dev, "vin-supply", &plat->vin_supply);
-	if (ret) {
-		debug("Regulator vin regulator not defined: %d\n", ret);
-		if (ret != -ENOENT)
-			return ret;
-	}
-
-	if (plat->vin_supply)
-		regulator_set_enable_if_allowed(plat->vin_supply, true);
-
 	return 0;
 }
 

drivers/power/regulator/regulator_common.h

@@ -14,7 +14,6 @@ struct regulator_common_plat {
 	unsigned int startup_delay_us;
 	unsigned int off_on_delay_us;
 	unsigned int enable_count;
-	struct udevice *vin_supply;
 };
 
 int regulator_common_of_to_plat(struct udevice *dev,