android/bluetooth: Add support for storing link keys
android/bluetooth: Add support for storing link keys

When new linkkey event is received store linkkey in devices info file.
Stored info includes linkkey, linkkey type and pin length.

ComputeCycles/bluez,silent-snowman/bluez,pstglia/external-bluetooth-bluez,ComputeCycles/bluez,pstglia/external-bluetooth-bluez,pkarasev3/bluez,silent-snowman/bluez,mapfau/bluez,pstglia/external-bluetooth-bluez,pkarasev3/bluez,mapfau/bluez,ComputeCycles/bluez,silent-snowman/bluez,pstglia/external-bluetooth-bluez,mapfau/bluez,pkarasev3/bluez,ComputeCycles/bluez,pkarasev3/bluez,silent-snowman/bluez,mapfau/bluez