scons: build the xorg state trackers only when env includes drm
diff --git a/src/gallium/SConscript b/src/gallium/SConscript
index 207987b..0efab83 100644
--- a/src/gallium/SConscript
+++ b/src/gallium/SConscript
@@ -116,7 +116,7 @@
             'targets/dri-r600/SConscript',
         ])
 
-if env['xorg']:
+if env['xorg'] and env['drm']:
     SConscript([
         #'targets/xorg-i915/SConscript',
         #'targets/xorg-i965/SConscript',