wifi: cfg80211: move enum ieee80211_ap_reg_power to cfg80211

This really shouldn't have been in ieee80211.h, since it
doesn't directly represent the spec. Move it to cfg80211
rather than mac80211 since upcoming changes will use it
there.

Reviewed-by: Miriam Rachel Korenblit <miriam.rachel.korenblit@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://msgid.link/20240523120945.962b16c831cd.I5745962525b1b176c5b90d37b3720fc100eee406@changeid


Signed-off-by: Johannes Berg <johannes.berg@intel.com>