ALSA: echoaudio: Prevent some noise on unloading the module

These are valid conditions in normal circumstances, so do not "warn" but
make them for debugging.

Signed-off-by: Mark Hills <mark@xwax.org>
Link: https://lore.kernel.org/r/20200708101848.3457-4-mark@xwax.org


Signed-off-by: Takashi Iwai <tiwai@suse.de>