Bluetooth: Host: ISO not clearing TX context on disconnect #77007
Description
** Describe the bug **
When disconnected while sending data, if ISO doesn't get the num of completed packets it will not call process_unack_tx and thus will leak TX context.
Fix that by setting the connection state in ISO disconnection which will trigger a call to process_unack_tx.
** To reproduce **
Create an ISO channel that will send data, disconnect before receiving the HCI number of completed packets event.
The following BabbleSim test reproduce the issue: theob-pro@e2d8225