[EGD-6514] HSP volume control

Bluetooth headset profile volume control
introduced. Small refactor on A2DP volume control
done.

[EGD-6882] Fix call hangup after BT device disconnect

Updated the BT stack with events that are handled through the
button so now it's possible to fallback to the earspeaker when
BT connection is lost

Added handling of those events

Merge branch 'master' into stable

[BH-378] PR changes

PR changes - mainly includes

[BH-378] Utils move log to library

Moved log to separate library

Merge branch 'master' into stable

[EGD-6049] Add voice call over HSP

Add support for voice calls over HSP.

Signed-off-by: Marcin Smoczyński <smoczynski.marcin@gmail.com>

[EGD-6447] Add Bluetooth PIN pairing

Implemented legacy pairing using PIN code

[EGD-6166] HSP ringing

Added HSP ring sound on incoming call event while
there's bluetooth connection active and HSP is
selected as the current profile.
Possibility of pick up/decline the call using
BT device buttons added.
Slightly changed HSP initialization according
to the UML-s added.
Changed call hangup handler in service cellular.

[EGD-6401] Fix bluetooth initialization

Fixed multiple initialization in A2DP and HSP profiles.

[EGD-6350] Added bluetooth device volume control

Bluetooth device volume control can be set by Pure Phone
while paired and is in A2DP mode. Temporarly disabled
HSP since it's not fully working and causing control issues.

[EGD-5260] Add A2DP playback to audio

Add basic playback capability using Bluetooth A2DP profile.
Only stereo/44100/16bit files are supported at the moment

Signed-off-by: Marcin Smoczyński <smoczynski.marcin@gmail.com>

[EGD-5945] Bluetooth-harness API messages

This PR:
* provides Bluetooth-Harness API messages definition [EGD-5944]
* provides Bluetooth-Harness API messages implementation
* provides Bluetooth-Harness API usage on harness side [EGD-5946]
* provides Bluetooth-Harness tests [EGD-5947]

[EGD-5954] Add CoD verification for bluetooth conn

Implement selective profile connection based on Class of Device

[EGD-6100] Add BT device turn off handling

After BT device disconnects (e.g. because of shutdown) Pure is now
aware of this

[EGD-6073] Fix text formatting in retry windows

Error message in retry windows was displayed incorrectly.

[EGD-6024] Return to All Devices window after attempt to retry action

Execution of retry pairing/unpairing/connecting took too long
to wait for it on retry popup. Fixed minor bugs.

[EGD-5984] Add BT implementation of added GUI actions

Implemented BT-side actions for GUI usage, e.g. connection status

[EGD-5940] Add BT device unpairing

Implemented possibility to forget/unpair a device via GUI

[EGD-5981] Fix BT scan stop issue

Btstack's scan stop call was not working properly thus force stop
function has been added