power: Always manage notify_on_migrate

Change-Id: I484b489dd0b71a7499d8f5d1a7ab0287d9af03f7
cmpower: Add support for set_interactive extension

 * Some devices might want to do custom stuff when the
   screen turns on/off. Add a hook for this.

Change-Id: If11fb34422bfcc776ae5ed48b43feb8468ca5d67
power: Fix locking and reference passing

 * DON'T CRASH!

Change-Id: I13f26259f7fa67e03c114446242037742925ded6
power: Remove recursive locking

 * Because of the stupid boostpulse thing, locking can work differently.
 * Will just move any set_interactive locking to the ext module

Change-Id: I27edcd6977f035a69464650e8587b6538b063316