mysql-5.1-innodb: add error codes to innodb_bug51920.test

kill of active connection yields different error code
depending on platform.

mysql-test/suite/innodb_plugin/r/innodb_bug51920.result

@@ -9,5 +9,5 @@ SELECT ID FROM INFORMATION_SCHEMA.PROCESSLIST
 WHERE INFO="UPDATE bug51920 SET i=2"
 INTO @thread_id;
 KILL @thread_id;
-ERROR 70100: Query execution was interrupted
+Got one of the listed errors
 DROP TABLE bug51920;