l2cap: fix create outgoing connection triggered in hci disconnect event callback

Avoids sending an ACL packet for a now non-existing HCI connection

l2cap: disconnect hci on l2cap connection request if ssp supported and link not encrypted in security mode 4

l2cap: disconnect hci on l2cap connection request if ssp supported and link not encrypted

l2cap: abort connection in secure connections only mode if legacy connection

l2cap: trigger authentication for outgoing ERTM connections

l2cap: use next signaling id for echo request

l2cap: make handling of hci disconnect more robust

l2cap: split l2cap_hci_event_handler

l2cap: push state check into l2cap_handle_disconnect_request

MISRAC2012-Rule-14.4_c: compare against 0 or NULL

fix build

l2cap: support de-init

l2cap: support ENABLE_EXPLICIT_CONNECTABLE_MODE_CONTROL

l2cap: fix packet size check for incoming classic basic channels (regression introduced in v1.2.1)

fix warnings for log_info/printf

l2cap: check packet size against local mtu for classic basic channels

l2cap: forward data only in open state

l2cap: use connection handle for channel lookup

l2cap.c, hfp_ag.c: remove duplicate function defintions

fix unused warnings

l2cap: trigger pairing for outgoing LE Data Channels if security level insufficient

add missing default switch cases

l2cap: streamline security level request for outgoing classic connections

MISRAC2012-Rule-10.4_a: append 'u' to constant literals when used in unsigned expressions or comparisons

remove <stdio.h>, <stdlib.h> and printf from most core files