sysdeps-win: Refactor cleanup of struct addrinfo during connect()
As suggested on !143 (merged). Instead of remembering to free it in every error condition, let's move its cleanup to the "out" phase so that it's done every time.
Change the iterator variable tmp to be const so that it's obvious we aren't meant to free that too.
@rhabacker, please could you test this on Windows?
!144 (merged) is the Unix equivalent of !143 (merged) + this.