Current snd_soc_pcm_runtime has platform / codec pointers, and we could
use these specific pointer. But these will be replaced to more generic
"component" soon, and will need more generic method to get each
connected component pointer from rtd.

This patch adds new snd_soc_rtdcom_xxx() to connect/disconnect
component to rtd. It means same as previous "platform" / "codec"
pointer style, but more generic.
We can find necessary component pointer from rtd by using component
driver name on snd_soc_rtdcom_lookup().

Here, the reason why it uses "driver name" is that "component name"
was created by fmt_single_name() and difficult to use it from driver.
Driver of course knows its "driver name", thus, using it is more easy.
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Tested-by: Arnaud Pouliquen <arnaud.pouliquen@st.com>
Signed-off-by: Mark Brown <broonie@kernel.org>