mt76: mt7615: remove leftover routine declaration

Get rid of mt76_dfs_start_rdd unused declaration
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

drivers/net/wireless/mediatek/mt76/mt7615/mt7615.h

@@ -342,7 +342,6 @@ void mt7615_mac_sta_remove(struct mt76_dev *mdev, struct ieee80211_vif *vif,
 void mt7615_mac_work(struct work_struct *work);
 void mt7615_txp_skb_unmap(struct mt76_dev *dev,
 			  struct mt76_txwi_cache *txwi);
-int mt76_dfs_start_rdd(struct mt7615_dev *dev, bool force);
 int mt7615_mcu_set_fcc5_lpn(struct mt7615_dev *dev, int val);
 int mt7615_mcu_set_pulse_th(struct mt7615_dev *dev,
 			    const struct mt7615_dfs_pulse *pulse);