ASoC: dt-bindings: meson: fix gx-card codec node regex

'codec' is a valid node name when there is a single codec
in the link. Fix the node regular expression to apply this.

Fixes: fd00366b ("ASoC: meson: gx: add sound card dt-binding documentation")
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230202183653.486216-3-jbrunet@baylibre.com


Signed-off-by: Mark Brown <broonie@kernel.org>