ALSA: lx_core: Remove dead code

Some code was never compiled because hidden between an #if 0 .. #endif
structure, and even when removing these, it was never actually used elsewhere.
Remove it entirely.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>