ARM: configs: Enable audio on BeagleBone Black in multi_v7_defconfig

The BeagleBone Black supports audio over HDMI, using a combination of the
DaVinci McASP (used for audio by a very large proportion of DaVinci systems
with audio support) and a TDA998x device driving the HDMI link (this is a
very widely used driver). Build both drivers as modules in multi_v7_defconfig
so they can be more easily included in testing.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Bartosz Golaszewski <brgl@bgdev.pl>
Link: https://lore.kernel.org/r/20220506222646.1671474-1-broonie@kernel.org'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>