Multiple radios/single phy - should the wiphy struct radios[] be set?

I've been trying to get a WCN6856 card working as an AP on OpenWrt (
but using a custom kernel and build ) and was hitting a brick wall
getting DBDC to work. I was starting from almost zero knowledge of
Linux WiFi in general which made it harder ( and means I might be
barking up the wrong tree ) - however, it seems that OpenWrt ( at
least ) relies on netlink returning a radio array to detect devices
that have multiple radios on a single phy, which doesn't seem
unreasonable to me.

I've hacked my OpenWrt build to assume that num_channels = 2 on a
second interface combination is the same thing ( which is what ath11k
seems to do when support_dual_stations is true) and confirmed that the
DBDC setup works with this mod. Shouldn't the ath11k driver be changed
to populate the radio list the same way ath12k does? What I've done
with OpenWrt is a bit of a hack, and who knows what else relies on
radios being defined!