Added module file dependancy information to the USB class drivers.

LUFA/Drivers/USB/Class/Device/Audio.h

LUFA/Drivers/USB/Class/Device/CDC.h

LUFA/Drivers/USB/Class/Device/HID.h

LUFA/Drivers/USB/Class/Device/MIDI.h

LUFA/Drivers/USB/Class/Device/MassStorage.h

LUFA/Drivers/USB/Class/Device/RNDIS.h

LUFA/Drivers/USB/Class/Host/Audio.h

LUFA/Drivers/USB/Class/Host/CDC.h

LUFA/Drivers/USB/Class/Host/HID.h

LUFA/Drivers/USB/Class/Host/HIDParser.h

LUFA/Drivers/USB/Class/Host/MIDI.h

LUFA/Drivers/USB/Class/Host/MassStorage.h

LUFA/Drivers/USB/Class/Host/StillImage.h