Nothing tests either symbol any more. AUDIO_SUPPORT was also selected by
PCI_SUPPORT and USB_SUPPORT, which stood for "a sound card could be
plugged in here": audio hardware sits behind MMC, SPI, a Bluetooth UART
or an SoC PCM block just as often, so the inference never held. The
display feature was derived from a literal CONFIG_VGA_CONSOLE or CONFIG_FB
in a kernel fragment, which misses every target whose fbdev came from DRM
emulation.
Delete both symbols, the two selects, the feature translations and the
derivation.
Signed-off-by: Daniel Golle <daniel@makrotopia.org>