iwlwifi: mvm: update the rssi calculation

Make the rssi more accurate by taking in count per-chain AGC
values. Without this, the RSSI reports inaccurate values.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/drivers/net/wireless/iwlwifi/mvm/fw-api.h b/drivers/net/wireless/iwlwifi/mvm/fw-api.h
index 23eebda..2adb61f 100644
--- a/drivers/net/wireless/iwlwifi/mvm/fw-api.h
+++ b/drivers/net/wireless/iwlwifi/mvm/fw-api.h
@@ -762,18 +762,20 @@
 #define IWL_RX_INFO_PHY_CNT 8
 #define IWL_RX_INFO_AGC_IDX 1
 #define IWL_RX_INFO_RSSI_AB_IDX 2
-#define IWL_RX_INFO_RSSI_C_IDX 3
-#define IWL_OFDM_AGC_DB_MSK 0xfe00
-#define IWL_OFDM_AGC_DB_POS 9
+#define IWL_OFDM_AGC_A_MSK 0x0000007f
+#define IWL_OFDM_AGC_A_POS 0
+#define IWL_OFDM_AGC_B_MSK 0x00003f80
+#define IWL_OFDM_AGC_B_POS 7
+#define IWL_OFDM_AGC_CODE_MSK 0x3fe00000
+#define IWL_OFDM_AGC_CODE_POS 20
 #define IWL_OFDM_RSSI_INBAND_A_MSK 0x00ff
-#define IWL_OFDM_RSSI_ALLBAND_A_MSK 0xff00
 #define IWL_OFDM_RSSI_A_POS 0
+#define IWL_OFDM_RSSI_ALLBAND_A_MSK 0xff00
+#define IWL_OFDM_RSSI_ALLBAND_A_POS 8
 #define IWL_OFDM_RSSI_INBAND_B_MSK 0xff0000
-#define IWL_OFDM_RSSI_ALLBAND_B_MSK 0xff000000
 #define IWL_OFDM_RSSI_B_POS 16
-#define IWL_OFDM_RSSI_INBAND_C_MSK 0x00ff
-#define IWL_OFDM_RSSI_ALLBAND_C_MSK 0xff00
-#define IWL_OFDM_RSSI_C_POS 0
+#define IWL_OFDM_RSSI_ALLBAND_B_MSK 0xff000000
+#define IWL_OFDM_RSSI_ALLBAND_B_POS 24
 
 /**
  * struct iwl_rx_phy_info - phy info