Fix Xephyr compilation without GLX.

configure.ac

@@ -1901,7 +1901,7 @@ if test "$KDRIVE" = yes; then
         XEPHYR=$xephyr
     fi
     XEPHYR_DRI=no
-    if test x$XEPHYR = xyes -a x$DRI = xyes; then
+    if test x$XEPHYR = xyes -a x$DRI = xyes && test "x$GLX" = xyes; then
         XEPHYR_DRI=yes
         XEPHYR_DRI_LIBS=-lGL
         AC_SUBST(XEPHYR_DRI_LIBS)

hw/kdrive/ephyr/ephyr.c

@@ -635,7 +635,9 @@ ephyrInitScreen (ScreenPtr pScreen)
   if (!ephyrNoDRI && !hostx_has_dri ()) {
       EPHYR_LOG ("host x does not support DRI. Disabling DRI forwarding\n") ;
       ephyrNoDRI = TRUE ;
+#ifdef GLXEXT
       noGlxVisualInit = FALSE ;
+#endif
   }
   if (!ephyrNoDRI) {
     ephyrDRIExtensionInit (pScreen) ;