ath10k: fix spelling in htt code comment

Fix spelling error.
Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

drivers/net/wireless/ath/ath10k/htt_rx.c

@@ -176,7 +176,7 @@ static void ath10k_htt_rx_msdu_buff_replenish(struct ath10k_htt *htt)
 	 * automatically balances load wrt to CPU power.
 	 *
 	 * This probably comes at a cost of lower maximum throughput but
-	 * improves the avarage and stability. */
+	 * improves the average and stability. */
 	spin_lock_bh(&htt->rx_ring.lock);
 	num_deficit = htt->rx_ring.fill_level - htt->rx_ring.fill_cnt;
 	num_to_fill = min(ATH10K_HTT_MAX_NUM_REFILL, num_deficit);