Fix "call" indicator value with multiple calls
Fix "call" indicator value with multiple calls

This indicator should go from 0 to 1 when the first call becomes active and
from 1 to zero when the last call goes idle.

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