xo-gc: refactor: retire DX1Collector._deep_move_gc_owned

xo-gc/include/xo/gc/DX1Collector.hpp

@@ -376,9 +376,9 @@ namespace xo {
              *  Require: runstate_.is_running()
              **/
             void * _deep_move_root(obj<AGCObject> from_src, Generation upto);
-#endif
             /** Common driver for _deep_move_root(), _deep_move_interior() **/
             void * _deep_move_gc_owned(void * from_src, Generation upto);
+#endif
             /** snap checkpoint containing allocator state
              *  use to detect forwarding activity after visiting objects
              **/

xo-gc/src/gc/DX1Collector.cpp

@@ -792,6 +792,7 @@ namespace xo {
         }
 #endif
 
+#ifdef OBSOLETE
         /*
          * rules:
          * - from_src must be in from-space
@@ -809,6 +810,7 @@ namespace xo {
         {
             return gco_store_._deep_move_gc_owned(this, from_src, upto);
         } /*_deep_move_gc_owned*/
+#endif
 
         auto
         DX1Collector::_snap_move_checkpoint(Generation upto) -> GCMoveCheckpoint