apps.intel_avf: free resources on shutdown (fix leak)
apps.intel_avf: free resources on shutdown (fix leak)

Free PCI resources and remaining packets on rx/tx queues on shutdown. This
fixes a resource leak.

eugeneia/snabb,SnabbCo/snabbswitch,snabbco/snabb,snabbco/snabb,SnabbCo/snabbswitch,Igalia/snabb,Igalia/snabb,snabbco/snabb,snabbco/snabb,SnabbCo/snabbswitch,snabbco/snabb,Igalia/snabb,eugeneia/snabb,snabbco/snabb,eugeneia/snabb,eugeneia/snabb,Igalia/snabb,snabbco/snabb,eugeneia/snabb,Igalia/snabb,Igalia/snabb,Igalia/snabb,eugeneia/snabb,eugeneia/snabb,Igalia/snabb,eugeneia/snabb,snabbco/snabb,SnabbCo/snabbswitch