Update app use for link of BR/EDR over GATT

Link of GATT over BR/EDR still exists when no app uses it.
To wait for the link down, closing bt takes more time.
This defect brought from change "Merge BT 4.1 features",
whose change-id is Ic6701da4cf6aaa390ff2c8816b43157f36b7fb42.

Give back link control using gatt_update_app_use_link_flag

Change-Id: Iee756f23651a32dcb7db1aed766e2c64dab6f6ea
Test: manual