600D audio meters fix
Created originally on Bitbucket by daniel_fort (Daniel Fort)
Was already merged in Bitbucket before import, marked as merged by the import user
The 600D needs Audio IC turned on at boot.
http://www.magiclantern.fm/forum/index.php?topic=15360.msg192480#msg192480
I also found some missing ASIF stubs for the 600D but didn't include them because they don't seem necessary.
#!c
NSTUB(0xFF06B9F4, PowerMicAmp)
NSTUB(0xFF058888, SetAudioVolumeIn)
NSTUB(0xFF057BE0, SoundDevActiveIn)
NSTUB(0xFF057C8C, SoundDevActiveOut) /* used instead of SoundDevShutDownIn on 600D */
// NSTUB(0xFF055840, StopASIFDMAADC) /* might break the audio meters */