Fixes a regression introduced by
5c009c17.

For IPV6 socket already bound with bind() with IPV6_V6ONLY set to 0
the address returned by getsockname() may change after it is connected
to a IPV4 peer (e. g., from :: to ::ffff:192.0.2.128).

The effect of blamed commit is that before that Unix getsockname()
was called for each ws2_32 getsockname() and after the commit the
socket name is cached at bind and connect.
Signed-off-by: Paul Gofman <pgofman@codeweavers.com>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>