ASoC: rt5651: Always keep OVCD enabled

OVCD is not only useful for jack-type detection, but is also useful
to protect against over-current faults in general, so always keep
OVCD enabled, instead of only enabling it for jack-type detection.

Tested-by: Carlo Caione <carlo@endlessm.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mark Brown <broonie@kernel.org>