ath9k_hw: define antenna diversity group

AR9285 belongs to diversity group 0 and AR9485 belongs to diversity
group 2. Based on the diversity group we configure certain antenna
diversity paramaters such as lna1_lna2_delta and fast diversity
bias values. For AR9485 we have some gain table parameter which
selects the gain table 0/1 for main and alternate antenna

Cc: Gabriel Tseng <Gabriel.Tseng@Atheros.com>
Cc: Senthilkumar Balasubramanian <Senthilkumar.Balasubramanian@Atheros.com>
Signed-off-by: Mohammed Shafi Shajakhan <mshajakhan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath9k/ar9002_phy.c b/drivers/net/wireless/ath/ath9k/ar9002_phy.c
index b4a0c1d..a57e963 100644
--- a/drivers/net/wireless/ath/ath9k/ar9002_phy.c
+++ b/drivers/net/wireless/ath/ath9k/ar9002_phy.c
@@ -529,6 +529,8 @@
 				 AR_PHY_9285_ANT_DIV_ALT_LNACONF_S;
 	antconf->fast_div_bias = (regval & AR_PHY_9285_FAST_DIV_BIAS) >>
 				  AR_PHY_9285_FAST_DIV_BIAS_S;
+	antconf->lna1_lna2_delta = -3;
+	antconf->div_group = 0;
 }
 
 static void ar9002_hw_antdiv_comb_conf_set(struct ath_hw *ah,