Boeffla: Apply values on boot only if nothing applied them before

This fixes a conflict with Boeffla Config V2 app, when DSP Manager would override already properly set values with other ones

Change-Id: I88c80dbc24a123837a9facf6b87dd5acda02a8d4
Merge branch 'kk-4.4' of https://github.com/TheSchismROM/android_packages_apps_DSPManager into kk-4.4