wil6210: interrupt: Demote comment header which is clearly not kernel-doc

Fixes the following W=1 kernel build warning(s):

 drivers/net/wireless/ath/wil6210/interrupt.c:652: warning: Function parameter or member 'irq' not described in 'wil6210_thread_irq'
 drivers/net/wireless/ath/wil6210/interrupt.c:652: warning: Function parameter or member 'cookie' not described in 'wil6210_thread_irq'

Cc: Maya Erez <merez@codeaurora.org>
Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: linux-wireless@vger.kernel.org
Cc: wil6210@qti.qualcomm.com
Cc: netdev@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200827073338.GS3248864@dell

drivers/net/wireless/ath/wil6210/interrupt.c

@@ -645,9 +645,7 @@ static irqreturn_t wil6210_irq_misc_thread(int irq, void *cookie)
 	return IRQ_HANDLED;
 }
 
-/**
- * thread IRQ handler
- */
+/* thread IRQ handler */
 static irqreturn_t wil6210_thread_irq(int irq, void *cookie)
 {
 	struct wil6210_priv *wil = cookie;