iwlagn: add .cfg flag to idenfity the need for bt statistics

Only WiFi/BT combo devices need to use bluetooth version of statistics
notification; adding the flag in .cfg file to indicate the need for
using different data structure.

Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
diff --git a/drivers/net/wireless/iwlwifi/iwl-core.h b/drivers/net/wireless/iwlwifi/iwl-core.h
index fcbba3d..2954a52 100644
--- a/drivers/net/wireless/iwlwifi/iwl-core.h
+++ b/drivers/net/wireless/iwlwifi/iwl-core.h
@@ -335,6 +335,7 @@
 	u8 scan_rx_antennas[IEEE80211_NUM_BANDS];
 	u8 scan_tx_antennas[IEEE80211_NUM_BANDS];
 	const bool need_dc_calib;
+	const bool bt_statistics;
 };
 
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