Allow 51MHz also when screen is on

Change-Id: I1bc5dbc8646cb45aaf799fb5bd1c374e4c1e7f30
Add cpu boost when waking up the device...

and also uncap the freq limit earlier.
This speeds up the wakeup routine quite a bit.

Change-Id: Ibd9635c8f576cc4846f074c012639e9993a54f8e