ASoC: Intel: sof_sdw_rt700: add codec prefix

Somehow for this codec we never used any prefix for the controls,
likely because the test platform has a single SoundWire device.

Follow the convention and use the codec prefix across the board to
avoid possible conflicts.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Link: https://lore.kernel.org/r/20200923080514.3242858-6-kai.vehmanen@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/intel/boards/sof_sdw_rt700.c

@@ -23,9 +23,9 @@ static const struct snd_soc_dapm_widget rt700_widgets[] = {
 
 static const struct snd_soc_dapm_route rt700_map[] = {
 	/* Headphones */
-	{ "Headphones", NULL, "HP" },
-	{ "Speaker", NULL, "SPK" },
-	{ "MIC2", NULL, "AMIC" },
+	{ "Headphones", NULL, "rt700 HP" },
+	{ "Speaker", NULL, "rt700 SPK" },
+	{ "rt700 MIC2", NULL, "AMIC" },
 };
 
 static const struct snd_kcontrol_new rt700_controls[] = {