Make sure that you have got the wireless driver from MediaTek or your distributor. If you flash the v3.x firmware of MT300N-V2, it should be fine as well.
Assume that you have known how to build a firmware, and you have built a firmware for MT300N-V2. We can execute this command to build our demonstration code.
make package/wlan_assoclist/{clean,compile} V=s
Further development
It is only contains a demonstration code to get wireless assoclist. You can integrate the function to your projet.