add support to link-local addresses

link-local addresses require interface name to be specified. For example a correct url with link-local ip would be the following: coap://[fe80::c63:43ed:a8ef:2ab3%wlx1cbfcedf85d7]:5683
We are using getnameinfo to get the correct interface name from the address. As a consequence, url query must be percent-encoded so that the base address is correctly decoded.

Commits:

• linux/communication: get_local_node_ip returns the first ip found
• linux/communication: add support to link-local addresses
• zephyr: set src_port to adapt to struct message_t changes

Signed-off-by: Francesco Pham francesco.pham@huawei.com