ath10k: advertise 10.4 fw ap and sta iface combination to mac80211

10.4 fw supports upto 16 interface in ap mode and 1 interface
in station mode, overall total interfaces supported are 16
interfaces. Populate this limit in wiphy->iface_combinations.

Signed-off-by: Raja Mani <rmani@qti.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>