Parts of TestUDPConnSpecificMethods and TestWriteToUDP fail, because
UDPConn.WriteMsgUDP is broken on Windows XP. UDPConn.WriteMsgUDP uses
Windows WSASendMsg API, but that call is not implemented on Windows XP (see
https://msdn.microsoft.com/en-us/library/windows/desktop/ms741692(v=vs.85).aspx
for details)

Update #23072

Change-Id: I4e8f149bc62bd87cd7c199e6832b9ce479af0a3e
Reviewed-on: https://go-review.googlesource.com/83077
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>