[PATCH setup] Link with -lws2_32 again

[Jon Turney]

On 20/03/2018 21:42, Yaakov Selkowitz wrote:
> libgpg-error 1.28 includes new APIs which use socket functions, which
> on Win32 are provided by WinSock2.
> 
> https://cygwin.com/ml/cygwin/2018-03/msg00306.html
> 
> Signed-off-by: Yaakov Selkowitz <yselkowi-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>

Thanks.  Applied.