ath9k: ar5008_hw_cmn_spur_mitigate: add missing mask_m & mask_p initialisation

by moving common code to ar5008_hw_cmn_spur_mitigate i forgot to move
mask_m & mask_p initialisation. This coused a performance regression
on ar9281.

Fixes: f911085f ("ath9k: split ar5008_hw_spur_mitigate and reuse common code in ar9002_hw_spur_mitigate.")
Reported-by: Gustav Frederiksen <lkml2017@openmailbox.org>
Tested-by: Gustav Frederiksen <lkml2017@openmailbox.org>
Cc: <stable@vger.kernel.org> # 4.2+
Signed-off-by: Oleksij Rempel <linux@rempel-privat.de>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/ath/ath9k/ar5008_phy.c

@@ -274,6 +274,9 @@ void ar5008_hw_cmn_spur_mitigate(struct ath_hw *ah,
 	};
 	static const int inc[4] = { 0, 100, 0, 0 };
 
+	memset(&mask_m, 0, sizeof(int8_t) * 123);
+	memset(&mask_p, 0, sizeof(int8_t) * 123);
+
 	cur_bin = -6000;
 	upper = bin + 100;
 	lower = bin - 100;
@@ -424,14 +427,9 @@ static void ar5008_hw_spur_mitigate(struct ath_hw *ah,
 	int tmp, new;
 	int i;
 
-	int8_t mask_m[123];
-	int8_t mask_p[123];
 	int cur_bb_spur;
 	bool is2GHz = IS_CHAN_2GHZ(chan);
 
-	memset(&mask_m, 0, sizeof(int8_t) * 123);
-	memset(&mask_p, 0, sizeof(int8_t) * 123);
-
 	for (i = 0; i < AR_EEPROM_MODAL_SPURS; i++) {
 		cur_bb_spur = ah->eep_ops->get_spur_channel(ah, i, is2GHz);
 		if (AR_NO_SPUR == cur_bb_spur)

drivers/net/wireless/ath/ath9k/ar9002_phy.c

@@ -178,14 +178,9 @@ static void ar9002_hw_spur_mitigate(struct ath_hw *ah,
 	int i;
 	struct chan_centers centers;
 
-	int8_t mask_m[123];
-	int8_t mask_p[123];
 	int cur_bb_spur;
 	bool is2GHz = IS_CHAN_2GHZ(chan);
 
-	memset(&mask_m, 0, sizeof(int8_t) * 123);
-	memset(&mask_p, 0, sizeof(int8_t) * 123);
-
 	ath9k_hw_get_channel_centers(ah, chan, &centers);
 	freq = centers.synth_center;