`show @@datasource` should base on hostname

[actiontech-bot]

Raised by: @zhunina

mysql> show @@datasource;
+----------+--------+--------------+------+------+--------+------+------+---------+-----------+------------+
| DATANODE | NAME   | HOST         | PORT | W/R  | ACTIVE | IDLE | SIZE | EXECUTE | READ_LOAD | WRITE_LOAD |
+----------+--------+--------------+------+------+--------+------+------+---------+-----------+------------+
| dn4      | hostM2 | 10.186.21.75 | 3306 | W    |      0 |    3 |  100 |   42936 |         2 |          0 |
| dn2      | hostM2 | 10.186.21.75 | 3306 | W    |      0 |    3 |  100 |   42936 |         2 |          0 |
| dn3      | hostM1 | 10.186.21.73 | 3306 | W    |      0 |    4 |  400 |   43049 |         3 |          0 |
| dn1      | hostM1 | 10.186.21.73 | 3306 | W    |      0 |    4 |  400 |   43049 |         3 |          0 |
+----------+--------+--------------+------+------+--------+------+------+---------+-----------+------------+

The statistic should base on hostname instead of dataname

[zhunina]

done