internal/poll, net: use (*FD).SetsockoptInet4Addr in setIPv4MulticastInterface on...

internal/poll, net: use (*FD).SetsockoptInet4Addr in setIPv4MulticastInterface on windows

Change-Id: Ic29d15bf62d8e693ca969354b415d958823bf41d
Reviewed-on: https://go-review.googlesource.com/c/go/+/523915
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
Auto-Submit: Tobias Klauser <tobias.klauser@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Damien Neil <dneil@google.com>