Change open_rx/tx_pcap/iface functions to open only a single pcap/dumper
and not loop num_of_queue times
The num_of_queue loop is already achieved by the
caller rte_kvargs_process
Fixing:
1. Opens N requested pcaps/dumpers instead of N^2
2. Leak of pcap/dumper's which are being overwritten by
the sequential calls to open_rx/tx_pcap/iface functions
3. Use the filename/iface args per queue and not just the last one
that overwrites the previous names