[Bug-wget] Remove set_windows_fd_as_blocking_socket()?

[Gisle Vanem]

A little study of why calling the function 'set_windows_fd_as_blocking_socket()' 
is needed, reveals that on downloading a big file (400MByte using ftp), the 
Winsock functions 'WSASetLastError()' and 'WSAGetLastError()' are called 
approx. 277.000 times!!  IMHO this is a terrible waste of CPU-time.

So I read a bit from the Gnulib bug-reports from 2011 on this:
 https://lists.gnu.org/archive/html/bug-gnulib/2011-04/msg00201.html

(the URL in mswindows.c seems a dead link). 

My test with disabling this function all together showed no ill effect.

I failed to find a Gnulib reference/changelog where this bug was fixed 
(after 2011), but reading some sources failed to find any place where 
a network-socket is set to blocking in Gnulib's select() or poll(). 

Hence I request that the call to 'set_windows_fd_as_blocking_socket()'
should be removed.

BTW. the actual call to Winsock's ioctlsocket() is performed by some 
hairy FD-hook stuff inside Gnulib if anybody wants to verify it.

--gv