ddl: move update version function to a proper place (#40817)

ref #40217

ddl/index.go

@@ -791,6 +791,9 @@ func doReorgWorkForCreateIndexMultiSchema(w *worker, d *ddlCtx, t *meta.Meta, jo
 		done, ver, err = doReorgWorkForCreateIndex(w, d, t, job, tbl, indexInfo)
 		if done {
 			job.MarkNonRevertible()
+			if err == nil {
+				ver, err = updateVersionAndTableInfo(d, t, job, tbl.Meta(), true)
+			}
 		}
 		// We need another round to wait for all the others sub-jobs to finish.
 		return false, ver, err
@@ -877,7 +880,6 @@ func doReorgWorkForCreateIndex(w *worker, d *ddlCtx, t *meta.Meta, job *model.Jo
 			return false, ver, err
 		}
 		indexInfo.BackfillState = model.BackfillStateInapplicable // Prevent double-write on this index.
-		ver, err = updateVersionAndTableInfo(d, t, job, tbl.Meta(), true)
 		return true, ver, err
 	default:
 		return false, 0, dbterror.ErrInvalidDDLState.GenWithStackByArgs("backfill", indexInfo.BackfillState)