Hi, I'm not familiar with your model, however - can you please post output of your dmesg? What happens if you install iw and wpad-mini? Also, have you tried checking whether the driver for your wireless isn't in one of the kmod-b43, kmod-brcm-wl or kmod-brcmfmac packages, that were not installed?
As far as I understand, wlan0 gets in openwrt created by netifd, if it has both wifi configuration, drivers and hostapd. If you're missing one of theese, it will not be created.