ath: Fix wrong function name in comments

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

 drivers/net/wireless/ath/hw.c:119: warning: expecting prototype for ath_hw_set_bssid_mask(). Prototype was for ath_hw_setbssidmask() instead

Signed-off-by: Yang Shen <shenyang39@huawei.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210517050141.61488-3-shenyang39@huawei.com

drivers/net/wireless/ath/hw.c

@@ -24,7 +24,7 @@
 #define REG_WRITE(_ah, _reg, _val)	(common->ops->write)(_ah, _val, _reg)
 
 /**
- * ath_hw_set_bssid_mask - filter out bssids we listen
+ * ath_hw_setbssidmask - filter out bssids we listen
  *
  * @common: the ath_common struct for the device.
  *