wifi: mac80211_hwsim: avoid calling nlmsg_free() in IRQ or IRQ disabled

wifi: mac80211_hwsim: avoid calling nlmsg_free() in IRQ or IRQ disabled

The nlmsg_free() ends up calling kfree_skb(), and kfree_skb() is not allowed to be called
from hardware interrupt context or with hardware interrupts being disabled. Replace the
mistaken usage of nlmsg_free() by dev_kfree_skb_irq(), which is safe in both cases.

Signed-off-by: EN-WEI WU <enweiwu@FreeBSD.org>
Link: https://lore.kernel.org/r/20230815095427.13589-1-enweiwu@FreeBSD.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>