Update test case

mysql-test/r/repair_symlink-5543.result

 create table t1 (a int) engine=myisam data directory='MYSQL_TMP_DIR';
 insert t1 values (1);
-# Some systems fail with errcode 40, when doing openat, while others
-# don't have openat and fail with errcode 20.
+# Some systems fail with errcode 40, or 90 (MIPS) when doing openat,
+# while others don't have openat and fail with errcode 20.
 repair table t1;
 Table	Op	Msg_type	Msg_text
 test.t1	repair	error	20 for record at pos 0