modify logfile directory structure

modify logfile directory structure

After one qtip test execution, the logfiles will be stored like this:

`-- 2017-03-09-17-40
    `-- node-41
        |-- dhrystone
        |   |-- inxi.log
        |   |-- node-41.zte.com.cn-2017-03-09-01
        |   |-- node-41.zte.com.cn-2017-03-09-01.html
        |   |-- node-41.zte.com.cn-2017-03-09-01.log
        |   `-- top.log
        |-- dpi
        |   |-- dpi_dump.txt
        |   |-- inxi.log
        |   `-- top.log
        |-- ramspeed
        |   |-- Floatmem
        |   |-- Intmem
        |   |-- inxi.log
        |   `-- top.log
        |-- ssl
        |   |-- AES-128-CBC_dump
        |   |-- RSA_dump
        |   |-- inxi.log
        |   `-- top.log
        `-- whetstone
            |-- inxi.log
            |-- node-41.zte.com.cn-2017-03-09-01
            |-- node-41.zte.com.cn-2017-03-09-01.html
            |-- node-41.zte.com.cn-2017-03-09-01.log
            `-- top.log

Change-Id: I5889a0e5dbe99f28212d6e0cdf69b9c03d89a9fe
Signed-off-by: wu.zhihui <wu.zhihui1@zte.com.cn>