RC: Add Superuser permission to manifest

Installer persistence uses su as of now, which leads to an
su prompt if settings are changed. This prompt displays the
big ugly red warning saying this permission is not declared.

Change-Id: I549796a151a8f171893bd600778d036beb657ab1
Signed-off-by: Rohan Mathur <rohanmathur34@gmail.com>
Feat: Allow users to disable safe headset volume warning (2/2)

Change-Id: Iebd2b04a47d241cd06202fcdbd12de10b29768ca
Signed-off-by: Dirk Rettschlag <dirk.rettschlag@gmail.com>