Fix avoid starting AVDTP disconnect timer twice
Fix avoid starting AVDTP disconnect timer twice

Remove starting the timer when setting the AVDTP state to idle. If
needed, the timer should probably already have been started in
avdtp_unref when the reference count goes to one.

Since reference counting is handled in avdtp_ref and avdtp_unref, it
seems reasonable that not to inspect the count outside of those
functions.

The issue was found when using Device.Disconnect to disconnect a
headset. It was revealed by commit
c72ce0f12a8387a70a6f0109f13bd6f414f32be8.

Before the commit, the timer was removed and then started again.
After applying it, the idle callback (disconnect_timeout) is called
twice, causing a crash.

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