force delete from place if there is no corresponding object in placex

This might happen for nameless landuse/natural objects that are added to place
during initial import but then dropped when being copied to placex.
If they later receive a name, thus becoming valid, then place_insert should
delete the orphan object in place and reinsert it. If they are large enough,
the place_delete trigger prevents them from being removed. The additional
update fools the delete trigger.

sql/functions.sql

@@ -2097,6 +2097,9 @@ BEGIN
   IF existingplacex.osm_type IS NULL THEN
 
     IF existing.osm_type IS NOT NULL THEN
+      -- pathological case caused by the triggerless copy into place during initial import
+      -- force delete even for large areas, it will be reinserted later
+      UPDATE place set geometry = ST_SetSRID(ST_Point(0,0), 4326) where osm_type = NEW.osm_type and osm_id = NEW.osm_id and class = NEW.class and type = NEW.type;
       DELETE from place where osm_type = NEW.osm_type and osm_id = NEW.osm_id and class = NEW.class and type = NEW.type;
     END IF;