[dts][PATCH V1 2/2] test_plans/generic_flow_api_test_plan: remove dpdk code modification.

[Tu, Lijuan]

> -    ./dpdk-testpmd -l
> 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,37,38,39,40,41,42,43,44,45,46,47,48,
> 49,50,51,52,53 -n 4 -- -i --disable-rss --rxq=128 --txq=128 --portmask=0x3 --nb-
> cores=4      --total-num-mbufs=263168
> +    ./dpdk-testpmd -l
> 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,37,38,39,40,41,42,43,44,45,46,47,48,
> 49,50,51,52,53 -n 4 -- -i --disable-rss --rxq=64 --txq=64 --portmask=0x3 --nb-
> cores=4      --total-num-mbufs=263168

''./dpdk-testpmd -l 1-5 is more reasonable, as only use 4 cores for pmd, and 1 core for eal, so totaling 5 cores are used.
List so many cores is not human friendly.

thanks