Bluetooth: Cleanup formatting and coding style

Fix some warnings and one error reported by checkpatch.pl:
- lines longer than 80 characters are wrapped
- empty lines inserted to separate variable declarations from the actual
  code
- line break inserted after if (...)

Co-developed-by: Thomas Röthenbacher <thomas.roethenbacher@fau.de>
Signed-off-by: Thomas Röthenbacher <thomas.roethenbacher@fau.de>
Signed-off-by: Fabian Schindlatz <fabian.schindlatz@fau.de>
Cc: linux-kernel@i4.cs.fau.de
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>