[bug report] regulator-fixed-domain can't sleep

[Konrad Dybcio]

Hello,

I've noticed that regulator-fixed-domain sets the performance state of the
attached genpd to 0 correctly, but will never actually let the power domain
it's attached to enter idle, as it has no PM ops. I was trying to come up
with a good set of PM ops, but I'm not sure what PM ops for a regulator
should look like.

Konrad