BT API security audit: fix a couple of permission mistakes.

Make functions that are meant to be BLUETOOTH_ADMIN really
BLUETOOTH_ADMIN.

Add some missing javadoc for permissions.

The only functional change here is the BLUETOOTH->BLUETOOTH_ADMIN
changes. This is super safe because every system app that uses BT
has both permissions.

Change-Id: Iddc61f9fd5d81fe0171358665a0fa52f2fa02871
DrNo: eastham
Joke: How do you catch a rabbit? Hide behind a tree and make carrott noises.