In order to access DHCP messages from clients in different states
and possibly to implement custom handlers that alter the current state,
e.g. reject a client with specific hostname using NAK.
* Extended storage for staipassigned events to pass client's MAC address.
* Added client's MAC to dhcp server callback
* Posting the staipassigned events with clients IP and MAC address
When client's request refused by sending NAK, its record still resided
in the linked list of pooled addresses. It is okay from the spec
perspective (RFC2131.p16: Server MAY mark the offered address
unavailable), but would consume some memory if the client didn't retry.
Closes https://github.com/espressif/esp-idf/issues/6410
1) kill_oldest_dhcps_pool() is only called when list has at least two members (assured with kconfig value limit), added assertion to ensure this function is used only when prerequisities are met
2) use after free reported in two places, since the analyzer checks also the scenario when the linked list has loops, added ignore tags
