Report tuple address in data-corruption error message

Most data-corruption reports mention the location of the problem, but
this one failed to.  Add it.

Backpatch all the way back.  In 12 and older, also assign the
ERRCODE_DATA_CORRUPTED error code as was done in commit fd6ec93 for
13 and later.

Discussion: https://postgr.es/m/202108191637.oqyzrdtnheir@alvherre.pgsql

Author: alvherre

src/backend/access/heap/heapam_handler.c

@@ -424,7 +424,11 @@ heapam_tuple_lock(Relation relation, ItemPointer tid, Snapshot snapshot,
 					if (TransactionIdIsValid(SnapshotDirty.xmin))
 						ereport(ERROR,
 								(errcode(ERRCODE_DATA_CORRUPTED),
-								 errmsg_internal("t_xmin is uncommitted in tuple to be updated")));
+								 errmsg_internal("t_xmin %u is uncommitted in tuple (%u,%u) to be updated in table \"%s\"",
+												 SnapshotDirty.xmin,
+												 ItemPointerGetBlockNumber(&tuple->t_self),
+												 ItemPointerGetOffsetNumber(&tuple->t_self),
+												 RelationGetRelationName(relation))));
 
 					/*
 					 * If tuple is being updated by other transaction then we