Merge branch 'opp/linux-next' of https://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm

Pull Operating Performance Points (OPP) framework updates for v4.16
from Viresh Kumar.

* 'opp/linux-next' of https://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm:
  OPP: Introduce "required-opp" property
  OPP: Allow OPP table to be used for power-domains