Changes

socket: osmo_sockaddr_from_str_and_uint(): fix memleak

`addrinfo_helper()` internally calls `getaddrinfo()`, whose result
must be freed with `freeaddrinfo()`.  On the size-check error path
the function returns early without freeing.  Fix this.

Change-Id: Ib05e1b8f2465e0db79e7b45de151dc9945e27924