mfd: cs42l43: Use devres for remove as well

mfd: cs42l43: Use devres for remove as well

Currently the device is powered down in the remove callback, however
all other clean up is done through devres. The problem here is the
MFD children are cleaned up through devres. As this happens after
the remove callback has run, this leads to the incorrect ordering
where the child remove functions run after the device has been powered
down. Put the power down into devres as well such that everything runs
in the expected order.

Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20241205115822.2371719-4-ckeepax@opensource.cirrus.com
Signed-off-by: Lee Jones <lee@kernel.org>