ASoC: soc-compress.c: fixup private_data on snd_soc_new_compress()

commit d3268a40 ("ASoC: soc-compress.c: fix NULL dereference")
enables DPCM capture, but it should independent from playback.
This patch fixup it.

Fixes: d3268a40 ("ASoC: soc-compress.c: fix NULL dereference")
Link: https://lore.kernel.org/r/87tu0i6j7j.wl-kuninori.morimoto.gx@renesas.com


Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Acked-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Link: https://lore.kernel.org/r/871qnkvo1s.wl-kuninori.morimoto.gx@renesas.com


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