Fix harmless compiler warnings about incomplete structure initializers.

FossilOrigin-Name: 604c11d1a39f09e47b6fcee0f8b1c1054f9dbbc7b2c1cf93312aeaa4b7095018

src/dbstat.c

@@ -694,6 +694,9 @@ int sqlite3DbstatRegister(sqlite3 *db){
     0,                            /* xRollback */
     0,                            /* xFindMethod */
     0,                            /* xRename */
+    0,                            /* xSavepoint */
+    0,                            /* xRelease */
+    0,                            /* xRollbackTo */
   };
   return sqlite3_create_module(db, "dbstat", &dbstat_module, 0);
 }