of /libdata/firmware and /usr/libdata/firmware are not installed
if set to "no". from the bsd.README:
MKFIRMWARE If "no", install the /libdata/firmware directory,
which is necessary for several drivers: athn(4), bwfm(4),
ipw(4), iwi(4), iwm(4), iwn(4), otus(4), rtwn(4), urtwn(4),
wpi(4), ral(4), rum(4), run(4), zyd(4), bcm43xx(4), and
the Tegra 124 SoC.
Default: yes on amd64, cobalt, evbarm evbmips, evbppc, hpcarm,
hppa, i386, mac68k, macppc, sandpoint, and sparc64, no elsewhere.
convert MKRADEONFIRMWARE and MKTEGRAFIRMWARE into FOO.arch lists,
and move their defaults above the general defaults setting.
saves about 12MB in a normal installation for other platforms.