ASoC: soc-pcm.c: remove unnecessary codec2codec_close_delayed_work()

commit 4bf2e385

 ("ASoC: core: Init pcm runtime work early to
avoid warnings") has added generic close_delayed_work() which checks
close_delayed_work_func

	static void close_delayed_work(...) {
		...
=>		if (rtd->close_delayed_work_func)
			rtd->close_delayed_work_func(rtd);
	}

So, we don't need to have NULL function for Codec2Codec.

=>	static void codec2codec_close_delayed_work()
	{
		/*
		 * Currently nothing to do for c2c links
		 * Since c2c links are internal nodes in the DAPM graph and
		 * don't interface with the outside world or application layer
		 * we don't have to do any special handling on close.
		 */
	}

	int soc_new_pcm(...)
	{
		...
		if (rtd->dai_link->params)
=>			rtd->close_delayed_work_func = codec2codec_close_delayed_work;
		else
			rtd->close_delayed_work_func = snd_soc_close_delayed_work;
		...
	}

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Link: https://lore.kernel.org/r/87sfle4dzk.wl-kuninori.morimoto.gx@renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>