tells whether it should detect and convert to binary a hexadecimal octet
string of the form 0x0123ABab, or leave those strings undecoded.
If the argument for a 'media', 'mediamode', 'mediaopt', '-mediaopt',
'nwkey', or 'bssid' keyword is a hexadecimal octet string, do not detect
and decode it. (Note that setifnwkey decodes hexadecimal strings on its
own.)
This fixes a bug noticed by Jim Miller where the trailing zero-octets
were discarded from hexadecimal octet-string arguments for 'nwkey'.