wifi: ieee80211: split NAN definitions out
The ieee80211.h file has gotten very long, continue splitting
it by putting NAN definitions into a separate file. Note that
NAN isn't really even IEEE 802.11 but WFA.
Link: https://patch.msgid.link/20251105153843.8da0e796dda2.I7b2ce11220b70e8794019501eabbf8afbaf431a6@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>