ASoC: remove .debugfs_prefix from Component

Kuninori Morimoto <kuninori.morimoto.gx@renesas.com> says:

Basically, we are assuming to use snd_soc_register_component() (X) to
register Component. It requests Component driver (A).

And, current Component has .debugfs_prefix (B).

Now we can set component->debugfs_prefix (B) via
component_driver->debugfs_prefix (A) today.

But some drivers are still trying to set it via (B).
Thus, they need to use snd_soc_component_initialize() (1) /
snd_soc_component_add() (2) instead of (X), because they need to
access component->debugfs_prefix (B).

These functions (= 1, 2) should be capsuled into soc-xxx.c, but can't
because of above drivers.

This patch-set removes component->debugfs_prefix (B).

The functions (= 1, 2) are still not yet be capsuled.
This is step1 for it, step2 will be posted after this.

Link: https://patch.msgid.link/87ldcxk5wz.wl-kuninori.morimoto.gx@renesas.com

diff --cc sound/soc/soc-core.c
Simple merge