[dts] [PATCH V1]virtio_pvp_regression: add retry when get dpdk promte to avoid print sequence issue

[Tu, Lijuan]

> Subject: [dts] [PATCH V1]virtio_pvp_regression: add retry when get dpdk promte
> to avoid print sequence issue
> 
> *. dpdk promte 'testpmd> ' might be misspelled when print
> 
> Signed-off-by: Xiao Qimai <qimaix.xiao at intel.com>
> ---
>  tests/TestSuite_virtio_pvp_regression.py | 9 ++++++++-

Applied