d3d10: Get rid of the unused idx_offset field from struct d3d10_effect_object.

dlls/d3d10/d3d10_private.h

@@ -69,7 +69,6 @@ struct d3d10_effect_object
 {
     struct d3d10_effect_pass *pass;
     enum d3d10_effect_object_type type;
-    DWORD idx_offset;
     DWORD index;
     void *data;
 };