bluez: Add pre-condition for sound through headphone jack

By default SabreLite board plays sound through HDMI connector.
In case tester want to output sound through headphone connector he should configure PulseAudio for it.

After the 2 first commands (set-default-sink and set-sink-port) the sound is heard correctly, but not after a reboot. This is due to mute state not saved at this time, this needs the third command (after reboot) to fix it.
Further reboot will play sound correctly.

Signed-off-by: Frédéric Danis frederic.danis@collabora.com