ASoC: SOF: Makefile - fix the top-level kernel module names (add snd- prefix)

Use the proper module name. The objs assignments are already there.

Signed-off-by: Jaroslav Kysela <perex@perex.cz>
Cc: Liam Girdwood <liam.r.girdwood@linux.intel.com>
Cc: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Mark Brown <broonie@kernel.org>0
Link: https://lore.kernel.org/r/20190725133743.22145-1-perex@perex.cz


Signed-off-by: Mark Brown <broonie@kernel.org>