regulator: rt4831: Add missing .owner field in regulator_desc

Add missing .owner field in regulator_desc, which is used for refcounting.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Message-Id: <20210524123735.2363676-1-axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@sirena.org.uk>