mac80211: fix 'reset' debugfs locking

cfg80211 now calls suspend/resume with the wiphy lock
held, and while there's a problem with that needing
to be fixed, we should do the same in debugfs.

Cc: stable@vger.kernel.org
Fixes: a05829a722 ("cfg80211: avoid holding the RTNL when calling the driver")
Link: https://lore.kernel.org/r/20210608113226.14020430e449.I78e19db0a55a8295a376e15ac4cf77dbb4c6fb51@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/debugfs.c

@@ -4,7 +4,7 @@
  *
  * Copyright 2007	Johannes Berg <johannes@sipsolutions.net>
  * Copyright 2013-2014  Intel Mobile Communications GmbH
- * Copyright (C) 2018 - 2019 Intel Corporation
+ * Copyright (C) 2018 - 2019, 2021 Intel Corporation
  */
 
 #include <linux/debugfs.h>
@@ -389,8 +389,10 @@ static ssize_t reset_write(struct file *file, const char __user *user_buf,
 	struct ieee80211_local *local = file->private_data;
 
 	rtnl_lock();
+	wiphy_lock(local->hw.wiphy);
 	__ieee80211_suspend(&local->hw, NULL);
 	__ieee80211_resume(&local->hw);
+	wiphy_unlock(local->hw.wiphy);
 	rtnl_unlock();
 
 	return count;