wifi: mac80211: validate HE 6 GHz operation when EHT is used

wifi: mac80211: validate HE 6 GHz operation when EHT is used

When in strict mode, validate that the HE 6 GHz operation is
valid even when EHT operation is used instead. This checks
that APs are advertising correct information for HE clients,
without testing with such clients.

Reviewed-by: Ilan Peer <ilan.peer@intel.com>
Reviewed-by: Miriam Rachel Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://patch.msgid.link/20260303150832.74b934163b99.If4d1db3f39c37900cf0d0f4669cd5f8b677daaa0@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>