iwlwifi: keep plcp_delta_threshold in priv

The base_params shouldn't be writable, so keep
a copy of this in priv that can be modified.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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-debugfs.c b/drivers/net/wireless/iwlwifi/iwl-debugfs.c
index b9b6d62..ade4134 100644
--- a/drivers/net/wireless/iwlwifi/iwl-debugfs.c
+++ b/drivers/net/wireless/iwlwifi/iwl-debugfs.c
@@ -2241,7 +2241,7 @@
 	const size_t bufsz = sizeof(buf);
 
 	pos += scnprintf(buf + pos, bufsz - pos, "%u\n",
-			cfg(priv)->base_params->plcp_delta_threshold);
+			priv->plcp_delta_threshold);
 
 	return simple_read_from_buffer(user_buf, count, ppos, buf, pos);
 }
@@ -2263,10 +2263,10 @@
 		return -EINVAL;
 	if ((plcp < IWL_MAX_PLCP_ERR_THRESHOLD_MIN) ||
 		(plcp > IWL_MAX_PLCP_ERR_THRESHOLD_MAX))
-		cfg(priv)->base_params->plcp_delta_threshold =
+		priv->plcp_delta_threshold =
 			IWL_MAX_PLCP_ERR_THRESHOLD_DISABLE;
 	else
-		cfg(priv)->base_params->plcp_delta_threshold = plcp;
+		priv->plcp_delta_threshold = plcp;
 	return count;
 }