gobex: Fix being able to cancel completed requests
gobex: Fix being able to cancel completed requests

This fixes bogus responses when rsp_func calls g_obex_cancel_req for
responses with final bit set.

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