This is needed since it might use (and pass out) pointers to
e.g. keys protected by RCU. Can't really happen here as the
frames aren't encrypted, but we need to still adhere to the
rules.

Fixes: cacfddf8 ("mac80211_hwsim: initialize ieee80211_tx_info at hw_scan_work")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://lore.kernel.org/r/20220505230421.5f139f9de173.I77ae111a28f7c0e9fd1ebcee7f39dbec5c606770@changeidSigned-off-by: Johannes Berg <johannes.berg@intel.com>