wifi: mac80211_hwsim: Fix possible NULL dereference

wifi: mac80211_hwsim: Fix possible NULL dereference

The 'vif' pointer in the Tx information might be NULL, e.g., in
case of injected frames etc. and is not checked in all paths. Fix it.
While at it, also directly use the local 'vif' pointer.

Fixes: a37a6f54439b ("wifi: mac80211_hwsim: Add simulation support for NAN device")
Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/linux-wireless/aNJUlyIiSTW9zZdr@stanley.mountain
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://patch.msgid.link/20251110140128.ec00ae795a32.I9c65659b52434189d8b2ba06710d482669a3887a@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>