staging: bcm2835-audio: remove compat ALSA card

Remove compat ALSA card, which has overlapping functionality with the
two other cards described by the driver (HDMI and headphones)

This handles TODO item "Revisit multi-cards options and PCM route mixer
control".

Move the S/PDIF device that was part of the compat ALSA card to the HDMI
card.

Only enable headphones card by default, because HDMI breaks when using
both vc4 and bcm2835-audio with HDMI card enabled.

Signed-off-by: Adrien Thierry <athierry@redhat.com>
Link: https://lore.kernel.org/r/20220408150359.26661-1-athierry@redhat.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>