Bluetooth: Return the correct address type for L2CAP sockets

Bluetooth: Return the correct address type for L2CAP sockets

The L2CAP sockets can use BR/EDR public, LE public and LE random
addresses for various combinations of source and destination
devices. So make sure that getsockname(), getpeername() and
accept() return the correct address type.

For this the address type of the source and destination is stored
with the L2CAP channel information. The stored address type is
not the one specific for the HCI protocol. It is the address
type used for the L2CAP sockets and the management interface.

The underlying HCI connections store the HCI address type. If
needed, it gets converted to the socket address type.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>