MINGW: Fix build with newest MinGW tool chain

Newest Win32 include files changed the include file order as compared to the
Microsoft MS compilers.

This is arguably a bug in the MinGW codebase, but working around it is too trivial
to complain about.

sim_sock.h

@@ -52,6 +52,7 @@ extern "C" {
 
 #if defined (_WIN32)                                    /* Windows */
 #include <winsock2.h>
+#include <winerror.h>
 
 #elif !defined (__OS2__) || defined (__EMX__)           /* VMS, Mac, Unix, OS/2 EMX */
 #include <sys/types.h>                                  /* for fcntl, getpid */