mac80211: remove channel_change_time

This value is no longer used by mac80211, and practically no
driver ever set it to a correct value anyway, so remove it.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

drivers/net/wireless/ath/ath5k/base.c

@@ -2549,7 +2549,6 @@ ath5k_init_ah(struct ath5k_hw *ah, const struct ath_bus_ops *bus_ops)
 	hw->wiphy->available_antennas_rx = 0x3;
 
 	hw->extra_tx_headroom = 2;
-	hw->channel_change_time = 5000;
 
 	/*
 	 * Mark the device as detached to avoid processing