Bluetooth: hci_conn: Fix running bis_cleanup for hci_conn->type PA_LINK

Connections with type of PA_LINK shall be considered temporary just to
track the lifetime of PA Sync setup, once the BIG Sync is established
and connection are created with BIS_LINK the existing PA_LINK
connection shall not longer use bis_cleanup otherwise it terminates the
PA Sync when that shall be left to BIS_LINK connection to do it.

Fixes: a7bcffc6 ("Bluetooth: Add PA_LINK to distinguish BIG sync and PA sync connections")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>