Platform will be replaced into Component in the future.
snd_soc_platform_driver has snd_pcm_ops, but snd_soc_component_driver
doesn't have it. To prepare for replacing, this patch adds snd_pcm_ops
on component driver.

platform will be replaced into component, and its code will be removed.
But during replacing, both platform and component process code exists.
To keep compatibility, to avoid platform NULL access and to avoid
platform/component duplicate operation during replacing process, this
patch has such code. Some of this code will be removed when platform was
removed.
Signed-off-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: NMark Brown <broonie@kernel.org>