iwm - Reduce gratuitous differences with Linux iwlwifi in struct naming.
- Rename some structs and struct members for firmware handling.
Submitted by: Augustin Cavalier <waddlesplash@gmail.com> (Haiku)
Obtained from: DragonFlyBSD (4b1006a6e4d0f61d48c67b46e1f791e30837db67)