WSAPoll: disabled on all windows builds

Due to WSAPoll bugs, libcurl does not work as intended. When the cURL
library is used to setup a connection to an incorrect port, normally the
result is CURLE_COULDNT_CONNECT, /* 7 */, but due to the bug in WSAPoll,
the result now is CURLE_OPERATION_TIMEDOUT, /* 28 - the timeout time was
reached */.

On August 1, Jan Koen Annot opened a case for this to Microsoft Premier
Online (https://premier.microsoft.com/).  The support engineer handling
the case wrote that the case description is quite clear.  He will try to
reproduce the issue and then proceed with troubleshooting it.

Reported by: Jan Koen Annot
Bug: http://curl.haxx.se/mail/lib-2012-07/0310.html

lib/select.h

@@ -7,7 +7,7 @@
  *                            | (__| |_| |  _ <| |___
  *                             \___|\___/|_| \_\_____|
  *
- * Copyright (C) 1998 - 2011, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2012, Daniel Stenberg, <daniel@haxx.se>, et al.
  *
  * This software is licensed as described in the file COPYING, which
  * you should have received as part of this distribution. The terms
@@ -30,24 +30,6 @@
 #include <poll.h>
 #endif
 
-/*
- * poll() function on Windows Vista and later is called WSAPoll()
- */
-
-#if defined(USE_WINSOCK) && (USE_WINSOCK > 1) && \
-    defined(_WIN32_WINNT) && (_WIN32_WINNT >= 0x0600)
-#  undef  HAVE_POLL
-#  define HAVE_POLL 1
-#  undef  HAVE_POLL_FINE
-#  define HAVE_POLL_FINE 1
-#  define poll(x,y,z) WSAPoll((x),(y),(z))
-#  if defined(_MSC_VER) && defined(POLLRDNORM)
-#    undef  POLLPRI
-#    define POLLPRI POLLRDBAND
-#    define HAVE_STRUCT_POLLFD 1
-#  endif
-#endif
-
 /*
  * Definition of pollfd struct and constants for platforms lacking them.
  */