[dts] [PATCH V1]test_plans/cvl_advanced_iavf_rss_gtpu_test_plan:remove steps of destroy rss rules for gtpu cases

[Tu, Lijuan]

> synced with developer, the behavior after destroy rss rules are not unified.
> so delete the steps after destroying rss rules.
> 
> Signed-off-by: qifu <qi.fu at intel.com>

Applied, thanks