(submit/xnest-config.h) mi: drop special include hack for Xnest

Now that Xnest is taking care of disbling unsupported extensions itself,
no more need for the special hack in here. Including xnest-config.h also
isn't needed anymore.

Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>

mi/miinitext.c

@@ -70,22 +70,13 @@ SOFTWARE.
  * the sale, use or other dealings in this Software without prior written
  * authorization from the copyright holder(s) and author(s).
  */
-
-#ifdef HAVE_DIX_CONFIG_H
 #include <dix-config.h>
-#endif
 
 #ifdef HAVE_XORG_CONFIG_H
 #include <xorg-config.h>
 #include "xf86Extensions.h"
 #endif
 
-#ifdef HAVE_XNEST_CONFIG_H
-#include <xnest-config.h>
-#undef COMPOSITE
-#undef DPMSExtension
-#endif
-
 #include "misc.h"
 #include "extension.h"
 #include "extinit_priv.h"