regulator: max77802: Don't treat OFF as an operating mode

The only operating modes that are supported by the regulators in the
max77802 PMIC are Output ON (normal) and Output On in Low Power Mode.
OFF was wrongly counted as an operating mode while is only a regulator
status. Make clear in the code that OFF is not an operating mode.

Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Mark Brown <broonie@kernel.org>