arm64: dts: meson: vim3l: remove sound card definition

The sound card definition should have been removed when the common
definition was added to the vim3 dtsi but this slips through.
Remove it now.

Fixes: 7c9c0624 ("arm64: dts: meson: vim3: make sound card common to all variants")
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Link: https://lore.kernel.org/r/20200828154435.419561-1-jbrunet@baylibre.com