Fix MySQL Test so it will not depend on current host in log file naming.

mysql-test/r/rpl_flush_log_loop.result

@@ -14,4 +14,4 @@ slave start;
 flush logs;
 show slave status;
 Master_Host	Master_User	Master_Port	Connect_retry	Master_Log_File	Read_Master_Log_Pos	Relay_Log_File	Relay_Log_Pos	Relay_Master_Log_File	Slave_IO_Running	Slave_SQL_Running	Replicate_do_db	Replicate_ignore_db	Last_errno	Last_error	Skip_counter	Exec_master_log_pos	Relay_log_space
-127.0.0.1	root	9307	60	slave-bin.001	79	mashka-relay-bin.001	119	slave-bin.001	Yes	Yes			0		0	79	119
+127.0.0.1	root	9307	60	slave-bin.001	79	relay-log.001	119	slave-bin.001	Yes	Yes			0		0	79	119

mysql-test/t/rpl_flush_log_loop-master.opt

--O max_binlog_size=1M
+-O max_binlog_size=1M  --relay-log=$MYSQL_TEST_DIR/var/master-data/relay-log

mysql-test/t/rpl_flush_log_loop-slave.opt

--O max_binlog_size=1M
+-O max_binlog_size=1M --relay-log=$MYSQL_TEST_DIR/var/slave-data/relay-log