ASoC: mediatek: mt8195: Add platform entry for ETDM1_OUT_BE dai link

Commit e70b8dd2 ("ASoC: mediatek: mt8195: Remove afe-dai component
and rework codec link") removed the codec entry for the ETDM1_OUT_BE
dai link entirely instead of replacing it with COMP_EMPTY(). This worked
by accident as the remaining COMP_EMPTY() platform entry became the codec
entry, and the platform entry became completely empty, effectively the
same as COMP_DUMMY() since snd_soc_fill_dummy_dai() doesn't do anything
for platform entries.

This causes a KASAN out-of-bounds warning in mtk_soundcard_common_probe()
in sound/soc/mediatek/common/mtk-soundcard-driver.c:

	for_each_card_prelinks(card, i, dai_link) {
		if (adsp_node && !strncmp(dai_link->name, "AFE_SOF", strlen("AFE_SOF")))
			dai_link->platforms->of_node = adsp_node;
		else if (!dai_link->platforms->name && !dai_link->platforms->of_node)
			dai_link->platforms->of_node = platform_node;
	}

where the code expects the platforms array to have space for at least one entry.

Add an COMP_EMPTY() entry so that dai_link->platforms has space.

Fixes: e70b8dd2

 ("ASoC: mediatek: mt8195: Remove afe-dai component and rework codec link")
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://patch.msgid.link/20240624061257.3115467-1-wenst@chromium.org
Signed-off-by: Mark Brown <broonie@kernel.org>