winebuild: Do not output an undefined symbol reference for variables.

tools/winebuild/import.c

@@ -508,7 +508,7 @@ static char *create_undef_symbols_file( DLLSPEC *spec )
     for (i = 0; i < spec->nb_entry_points; i++)
     {
         ORDDEF *odp = &spec->entry_points[i];
-        if (odp->type == TYPE_STUB || odp->type == TYPE_ABS) continue;
+        if (odp->type == TYPE_STUB || odp->type == TYPE_ABS || odp->type == TYPE_VARIABLE) continue;
         if (odp->flags & FLAG_FORWARD) continue;
         fprintf( f, "\t%s %s\n", get_asm_ptr_keyword(), asm_name(odp->link_name) );
     }