ath9k_hw: Fix tx power settings for AR9003

Retriving tx power for 2x2 and 3x3 chainmask is not handled
properly. While calculating tx power for 2x2, 3 dBm was reduced
and for 3x3, 5 dBm was reduced which should be added back when
retriving.

Cc: Paul Stewart <pstew@google.com>
Signed-off-by: NRajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/ath9k/ar9003_eeprom.c

@@ -5059,6 +5059,8 @@ static void ath9k_hw_ar9300_set_txpower(struct ath_hw *ah,
 			regulatory->max_power_level = targetPowerValT2[i];
 	}
 
+	ath9k_hw_update_regulatory_maxpower(ah);
+
 	if (test)
 		return;