regulator: bd718x7: remove voltage change restriction from BD71847

regulator: bd718x7: remove voltage change restriction from BD71847

The BD71837 had a HW "feature" where changing the regulator output
voltages of other regulators but bucks 1-4 might cause spikes if
regulators were enabled. Thus SW prohibit voltage changes for other
regulators except for bucks 1-4 when regulator is enabled.

The HW colleagues did inadvertly fix this issue for BD71847 and
BD71850. Remove voltage change restrictions from other PMICs but
BD71837.

The LDO voltage changing is still restricted. I did not yet receive
answer whether there is voltage spikes to be expected for LDOs. I
only know that the power-good detection for LDOs can cause false
alarms if LDO voltage is changed when LDO is enabled. We might be
able to work-around this by disabling the power-good monioring for
the duration of the LDO voltage change - but as I said, I don't
know yet. Let's fix it later if we can confirm that also LDO voltage
changes are safe.

Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Link: https://lore.kernel.org/r/20200428092930.GA9721@localhost.localdomain
Signed-off-by: Mark Brown <broonie@kernel.org>