I really suggest that you don't change ANYTHING at this point. Wait until you gain legal status to begin the process of changing your name. The whole immigration system will be changed completely if Congress pass CIR this year, which means things will get messy and complicated and the last thing you want especially now is to mess around. Whatever name that is on all of your DACA documents as well as your passport and birth certificate, its the name that you should stay with for now. Thats just my suggestion.