doc: Update descriptions and possible error returns of mgmt commands
doc: Update descriptions and possible error returns of mgmt commands

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