ath10k-ct: Add htt-mgt variants of ath10k-ct firmware.

ath10k-ct: Add htt-mgt variants of ath10k-ct firmware.

The HTT-MGT variants transport management frames over the
normal HTT tx path, just like data frames.  This saves
limitted WMI buffers which can become depleted if lots of
management frames become stuck in TX queues due to peer
that went away.

In addition, at least for the wave-1 firmware, htt-mgt is
required in order for 802.11r (fast roaming) authentication
to function properly.

The htt-mgt firmware requires the use of the ath10k-ct
driver.  Normal non-htt-mgt ath10k-ct firmware should work
with stock drivers.

Signed-off-by: Ben Greear <greearb@candelatech.com>