check find_adapter return value for NULL
check find_adapter return value for NULL

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