regulator/core: Revert "fix kobject release warning and memory leak in regulator_register()"

This reverts commit 5f4b204b

.

Since rdev->dev now has a release() callback, the proper way of freeing
the initialized device can be restored.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Link: https://lore.kernel.org/r/d7f469f3f7b1f0e1d52f9a7ede3f3c5703382090.1695077303.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown <broonie@kernel.org>