Merge branch 'pm-opp'

* pm-opp:
  PM / OPP: passing NULL to PTR_ERR()
  PM / OPP: Move cpu specific code to opp/cpu.c
  PM / OPP: Move opp core to its own directory
  PM / OPP: Prefix exported opp routines with dev_pm_opp_
  PM / OPP: Rename opp init/free table routines
  PM / OPP: reuse of_parse_phandle()