intel_th: pti: Use sysfs_match_string() helper

Use sysfs_match_string() helper instead of open coded variant.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>

drivers/hwtracing/intel_th/pti.c

@@ -272,19 +272,17 @@ static ssize_t lpp_dest_store(struct device *dev, struct device_attribute *attr,
 			      const char *buf, size_t size)
 {
 	struct pti_device *pti = dev_get_drvdata(dev);
-	ssize_t ret = -EINVAL;
 	int i;
 
-	for (i = 0; i < ARRAY_SIZE(lpp_dest_str); i++)
-		if (sysfs_streq(buf, lpp_dest_str[i]))
-			break;
+	i = sysfs_match_string(lpp_dest_str, buf);
+	if (i < 0)
+		return i;
 
-	if (i < ARRAY_SIZE(lpp_dest_str) && pti->lpp_dest_mask & BIT(i)) {
-		pti->lpp_dest = i;
-		ret = size;
-	}
+	if (!(pti->lpp_dest_mask & BIT(i)))
+		return -EINVAL;
 
-	return ret;
+	pti->lpp_dest = i;
+	return size;
 }
 
 static DEVICE_ATTR_RW(lpp_dest);