Rename the callback from ath9k_chanctx_force_active()
to ath9k_mgd_prepare_tx(). Also, move it to main.c and
group it with the other callbacks.
Signed-off-by: NSujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>