socket.c: use rb_syserr_fail

* ext/socket/socket.c (rsock_syserr_fail_host_port): add errno
  argument version anduse rb_syserr_fail_str() instead of
  rb_sys_fail_str() with restoring errno.
* ext/socket/socket.c (rsock_syserr_fail_path): ditto, and
  rb_syserr_fail().
* ext/socket/socket.c (rsock_sys_fail_sockaddr): ditto, use
  rsock_syserr_fail_raddrinfo().
* ext/socket/socket.c (rsock_sys_fail_raddrinfo): ditto.
* ext/socket/socket.c (setup_domain_and_type): ditto.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@44496 b2dd03c8-39d4-4d8f-98ff-823fe69b080e