Audio_Enable, AVR template update (#8901)

* Branch point for 2020 May 30 Breaking Change

* audio-configuration: template: audio_avr.c does NOT default to C6

not on its own, it needs a pin configured per define in config.h for audio to actually work
otherwise only parts of the code are included in the firmware, wasting space and possibly breaking builds because auf hitting the firmware-size limits

* audio-configuration: strip comment to bare essentials

Co-Authored-By: Ryan <fauxpark@gmail.com>

* revert future change

Co-authored-by: James Young <18669334+noroadsleft@users.noreply.github.com>
Co-authored-by: Johannes <you@example.com>
Co-authored-by: Ryan <fauxpark@gmail.com>
Co-authored-by: zvecr <git@zvecr.com>

quantum/template/avr/rules.mk

@@ -27,6 +27,6 @@ BACKLIGHT_ENABLE = no       # Enable keyboard backlight functionality
 RGBLIGHT_ENABLE = no        # Enable keyboard RGB underglow
 MIDI_ENABLE = no            # MIDI support
 BLUETOOTH_ENABLE = no       # Enable Bluetooth with the Adafruit EZ-Key HID
-AUDIO_ENABLE = no           # Audio output on port C6
+AUDIO_ENABLE = no           # Audio output
 FAUXCLICKY_ENABLE = no      # Use buzzer to emulate clicky switches
 HD44780_ENABLE = no         # Enable support for HD44780 based LCDs