iwm - Improve firmware Time Event handling.
- This is a mix of the OpenBSD Git 7fd9664469d1b717a307eebd74aeececbd3c41cc
change, and syncing with the Linux iwlwifi code.
Taken-From: Linux iwlwifi, and OpenBSD
Submitted by: Augustin Cavalier <waddlesplash@gmail.com> (Haiku)
Obtained from: DragonFlyBSD (706a3044afd27c3fecfdf57bec1695310e53e228)