Bluetooth: SMP: Fix crash when receiving new connection when debug is enabled

Bluetooth: SMP: Fix crash when receiving new connection when debug is enabled

commit 995fca15b73ff8f92888cc2d5d95f17ffdac74ba upstream.

When receiving a new connection pchan->conn won't be initialized so the
code cannot use bt_dev_dbg as the pointer to hci_dev won't be
accessible.

Fixes: 2e1614f7d61e4 ("Bluetooth: SMP: Convert BT_ERR/BT_DBG to bt_dev_err/bt_dev_dbg")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>