iwlwifi: add bt_init_traffic_load as configurable parameter

Adding configurable parameter in .cfg for the initial Bluetooth traffic
load; set it to IWL_BT_COEX_TRAFFIC_LOAD_NONE for now, but can be change
for debugging or other reason.

Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/iwlwifi/iwl-agn.c b/drivers/net/wireless/iwlwifi/iwl-agn.c
index c17ce82..06e89d4 100644
--- a/drivers/net/wireless/iwlwifi/iwl-agn.c
+++ b/drivers/net/wireless/iwlwifi/iwl-agn.c
@@ -2805,7 +2805,7 @@
 	iwl_clear_driver_stations(priv);
 
 	/* reset BT coex data */
-	priv->bt_traffic_load = 0;
+	priv->bt_traffic_load = priv->cfg->bt_init_traffic_load;
 	priv->bt_sco_active = false;
 	priv->bt_full_concurrent = false;
 	priv->bt_ci_compliance = 0;