Add support for Huntington MCDI licensing interface to common code.
Ported from Linux net driver IOCTL functions with restructuring for
initial support for V3 licensing API.
Submitted by: Richard Houldsworth <rhouldsworth at solarflare.com>
Reviewed by: gnn
Sponsored by: Solarflare Communications, Inc.
MFC after: 2 days
Differential Revision: https://reviews.freebsd.org/D4918