Bluetooth: hci_conn: Fix not setting conn_timeout for Broadcast Receiver

Broadcast Receiver requires creating PA sync but the command just
generates a status so this makes use of __hci_cmd_sync_status_sk to wait
for HCI_EV_LE_PA_SYNC_ESTABLISHED, also because of this chance it is not
longer necessary to use a custom method to serialize the process of
creating the PA sync since the cmd_work_sync itself ensures only one
command would be pending which now awaits for
HCI_EV_LE_PA_SYNC_ESTABLISHED before proceeding to next connection.

Fixes: 4a5e0ba6 ("Bluetooth: ISO: Do not emit LE PA Create Sync if previous is pending")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>