ASoC: SOF: ipc4-mtrace: prevent underflow in sof_ipc4_priority_mask_dfs_write()

The "id" comes from the user.  Change the type to unsigned to prevent
an array underflow.

Fixes: f4ea22f7 ("ASoC: SOF: ipc4: Add support for mtrace log extraction")
Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Link: https://lore.kernel.org/r/Y8laruWOEwOC/dx9@kiliSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/sof/ipc4-mtrace.c

@@ -344,9 +344,10 @@ static ssize_t sof_ipc4_priority_mask_dfs_write(struct file *file,
 						size_t count, loff_t *ppos)
 {
 	struct sof_mtrace_priv *priv = file->private_data;
-	int id, ret;
+	unsigned int id;
 	char *buf;
 	u32 mask;
+	int ret;
 
 	/*
 	 * To update Nth mask entry, write:
@@ -357,9 +358,9 @@ static ssize_t sof_ipc4_priority_mask_dfs_write(struct file *file,
 	if (IS_ERR(buf))
 		return PTR_ERR(buf);
 
-	ret = sscanf(buf, "%d,0x%x", &id, &mask);
+	ret = sscanf(buf, "%u,0x%x", &id, &mask);
 	if (ret != 2) {
-		ret = sscanf(buf, "%d,%x", &id, &mask);
+		ret = sscanf(buf, "%u,%x", &id, &mask);
 		if (ret != 2) {
 			ret = -EINVAL;
 			goto out;