Bluetooth: hci_conn: fail SCO/ISO via hci_conn_failed if ACL gone early

In the Linux kernel, the following vulnerability has been resolved:

Bluetooth: hci_conn: fail SCO/ISO via hci_conn_failed if ACL gone early

Not calling hci_(dis)connect_cfm before deleting conn referred to by a socket generally results to use-after-free.

When cleaning up SCO connections when the parent ACL is deleted too early, use hci_conn_failed to do the connection cleanup properly.

We also need to clean up ISO connections in a similar situation when connecting has started but LE Create CIS is not yet sent, so do it too here.