Revert "Bluetooth: Revert: Fix L2CAP connection establishment"

This reverts commit 4dff523a.

It was reported that this patch cause issues when trying to connect to
legacy devices so reverting it.
Reported-by: NDavid Fries <david@fries.net>
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>

net/bluetooth/hci_conn.c

@@ -673,7 +673,7 @@ int hci_conn_security(struct hci_conn *conn, __u8 sec_level, __u8 auth_type)
 		goto encrypt;
 
 auth:
-	if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &conn->pend))
+	if (test_bit(HCI_CONN_ENCRYPT_PEND, &conn->pend))
 		return 0;
 
 	if (!hci_conn_auth(conn, sec_level, auth_type))