ALSA: pci/ctxfi: fix kernel-doc warnings

Fix W=1 warnings. The files contain formatting that isn't kernel-doc.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200702193604.169059-10-pierre-louis.bossart@linux.intel.com


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