ASoC: wm_adsp: wm_adsp_control_add() error: uninitialized symbol 'ret'

This patch fixes the static analysis warning as it is correctly
indicating a possible code path, it cannot know that for the affected
firmware versions subname would always be NULL.
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Simon Trimmer <simont@opensource.cirrus.com>
Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20211115120154.56782-1-simont@opensource.cirrus.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/codecs/wm_adsp.c

@@ -617,8 +617,9 @@ static int wm_adsp_control_add(struct cs_dsp_coeff_ctl *cs_ctl)
 	switch (cs_dsp->fw_ver) {
 	case 0:
 	case 1:
-		snprintf(name, SNDRV_CTL_ELEM_ID_NAME_MAXLEN, "%s %s %x",
-			 cs_dsp->name, region_name, cs_ctl->alg_region.alg);
+		ret = scnprintf(name, SNDRV_CTL_ELEM_ID_NAME_MAXLEN,
+				"%s %s %x", cs_dsp->name, region_name,
+				cs_ctl->alg_region.alg);
 		break;
 	case 2:
 		ret = scnprintf(name, SNDRV_CTL_ELEM_ID_NAME_MAXLEN,