Add script to convert wpa_supplicant debug output to pcap

Add script to convert wpa_supplicant debug output to pcap

For debugging I needed to look at the frames in a wpa_supplicant debug
log. Looking at the hexdump is a bit tedious, so I wrote a quick script
to convert the nl80211 debugging output to a PCAP file that can be
opened in wireshark.

I've polished the initial raw script a bit to add error messages and to
also record the timestamps to the pcap file.

Hopefully it's useful to somebody else as well.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>