Fix a mtr warning in innodb_plugin.innodb-autoinc

mysql-test/suite/innodb_plugin/t/innodb-autoinc.test

@@ -2,6 +2,8 @@
 # embedded server ignores 'delayed', so skip this
 -- source include/not_embedded.inc
 
+let $innodb_file_format_check_orig=`select @@innodb_file_format_check`;
+
 --disable_warnings
 drop table if exists t1;
 --enable_warnings
@@ -662,3 +664,10 @@ INSERT INTO  t1 VALUES (1), (2), (-685113344), (NULL);
 SELECT * FROM t1;
 SHOW CREATE TABLE t1;
 DROP TABLE t1;
+
+#
+# restore environment to the state it was before this test execution
+#
+
+-- disable_query_log
+eval set global innodb_file_format_check=$innodb_file_format_check_orig;