ath11k: Fix typo in comments

There is a typo(isn't') in comments.
It maybe 'isn't' instead of 'isn't''.
Signed-off-by: Zhang Jiaming <jiaming@nfschina.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20220704030004.16484-1-jiaming@nfschina.com

drivers/net/wireless/ath/ath11k/hal.c

@@ -1165,7 +1165,7 @@ void ath11k_hal_srng_shadow_update_hp_tp(struct ath11k_base *ab,
 	lockdep_assert_held(&srng->lock);
 
 	/* check whether the ring is emptry. Update the shadow
-	 * HP only when then ring isn't' empty.
+	 * HP only when then ring isn't empty.
 	 */
 	if (srng->ring_dir == HAL_SRNG_DIR_SRC &&
 	    *srng->u.src_ring.tp_addr != srng->u.src_ring.hp)