BBCH_BBCHEN_MASK is equivalent to TPS65910_SUPPLY_STATE_ENABLED.
So all regulators have the same enable_mask setting.

BBCH_BBCHEN_MASK and BBCH_BBCHEN_SHIFT are not used now, remove them.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@linaro.org>