regulator: debug early supply resolving

Help debugging the case when set_machine_constraints() needs to be
repeated.
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Tested-by: Ahmad Fatoum <a.fatoum@pengutronix.de> # stpmic1
Link: https://lore.kernel.org/r/f9cba575580369e46661a9278ee6c6a8d8564c2a.1605226675.git.mirq-linux@rere.qmqm.plSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/regulator/core.c

@@ -5299,6 +5299,8 @@ regulator_register(const struct regulator_desc *regulator_desc,
 		/* FIXME: this currently triggers a chicken-and-egg problem
 		 * when creating -SUPPLY symlink in sysfs to a regulator
 		 * that is just being created */
+		rdev_dbg(rdev, "will resolve supply early: %s\n",
+			 rdev->supply_name);
 		ret = regulator_resolve_supply(rdev);
 		if (!ret)
 			ret = set_machine_constraints(rdev, constraints);