LinuxKPI: 802.11 header updates and add/adjust source dependencies.

This update is for more/newer versions of drivers:

• add and properly place more structs, enums, defines needed by drivers.
• correct types of struct fields.
• make various function arguments const.
• move REG_RULE() macro to its own file regulatory.h and use macros for calculations.
• add linuxkpi_ieee80211_get_channel() implementation.
• change linuxkpi_ieee80211_ifattach() to return int for error checking.

No intended functional changes for iwlwifi.

Sponsored by: The FreeBSD Foundation (partially)
MFC after: 3 days