This can be used by external programs (e.g., wlantest_cli) to inject
raw frames (hex dump of the frame header and body). The data can be
requested to be sent as-is or protected with the current key.
This adds new commands for wlantest_cli to request wlantest to
inject frames. This version can only send out Authentication
frames and unprotected SA Query Request frames, but there is
now place to add more frames and encryption with future commits.