The use of the pcap subdirectory seems to be limited to some of the
newer Linux distros only, so use the older paths to pcap.h and
pcap-bpf.h to make wlantest bit more easier to compile on older
systems.
The output file includes all the capture (or read from wireless PCAP
file) frames in their original contents and another copy of each
frame that is decrypted in wlantest (including EAPOL-Key Key Data
field).