[dts][PATCH V2 2/4] tests/vf_vlan: update dts code for driver change

[Tu, Lijuan]

> The out-tree driver has vf-vlan-pruning option,but in-tree driver has not. So we need different action to
> enable vlan filter when we validate the vlan filter function with in-tree and out-tree kernel drvier.
> 
> Signed-off-by: Weiyuan Li <weiyuanx.li at intel.com>

I don't think it's a good idea to assume out of tree driver support vf-vlan-pruning and in tree drives don't support it.
As time goes on, the feature might be supported by in tree driver.