net80211: add initial AES-GCMP crypto support

This adds initial AES-GCMP crypto support. It registers for both
128 and 256 bit support, although the 256 bit support will not work
without extending the net80211/ioctl keylength.

This is not yet enabled by default; drivers will need to opt-in
to supporting it in either hardware or software.

The AES-GCMP code is BSD licenced code from hostapd.git release 2.11.

Differential Revision: https://reviews.freebsd.org/D49161