[][MAC80211][WiFi6][mt76][Add obss_interval config add with ht_coex]

[Description]
Add obss_interval config add with ht_coex.

[Release-log]
N/A

Change-Id: Ic841aacefb6b1e83135a35d7a840a518308d3393
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/7962958
1 file changed