winsock2.h must always be included before windows.h

Some GNULIB headers (eg unistd.h) will often need to include
winsock2.h for various symbols. There is a rule that winsock2.h
must be included before windows.h. This means that any file
which does

  #ifdef WIN32
  #include <windows.h>
  #endif
  #include <unistd.h>

is potentially broken. A simple rule is that /all/ includes of
windows.h must be matched with a preceding include of winsock2.h
regardless of whether unistd.h is used currently
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

src/util/util.c

@@ -65,6 +65,9 @@
 #endif
 
 #ifdef WIN32
+# ifdef HAVE_WINSOCK2_H
+#  include <winsock2.h>
+# endif
 # include <windows.h>
 # include <shlobj.h>
 #endif

src/vbox/vbox_MSCOMGlue.c

@@ -22,6 +22,9 @@
 
 #include <config.h>
 
+#ifdef HAVE_WINSOCK2_H
+# include <winsock2.h>
+#endif
 #include <windows.h>
 
 #define nsCID CLSID