Fix: ED_view3d_depth_override cannot disable overlays

Change from ababc2e01b did not actually behave in a way that the
caller can force-disable overlays [which seems like the intention from
the commit message and also desired behavior for e.g. grease pencil
drawing/reprojecion].

Pull Request: https://projects.blender.org/blender/blender/pulls/131861

source/blender/editors/space_view3d/view3d_draw.cc

@@ -2400,8 +2400,8 @@ void ED_view3d_depth_override(Depsgraph *depsgraph,
     use_overlay = false;
   }
 
-  if (use_overlay) {
-    v3d->flag2 &= ~V3D_HIDE_OVERLAYS;
+  if (!use_overlay) {
+    v3d->flag2 |= V3D_HIDE_OVERLAYS;
   }
 
   /* Tools may request depth outside of regular drawing code. */