backlight: use kstrtoul()

The usage of simple_strtoul() or strict_strtoul() is not preferred.  Thus,
kstrtoul should be used.

This patch also fixes checkpatch error as follows:
ERROR: space required after that ',' (ctx:VxV)

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c
index 7363c1b..bf5b1ec 100644
--- a/drivers/video/backlight/backlight.c
+++ b/drivers/video/backlight/backlight.c
@@ -102,7 +102,7 @@
 }
 
 static ssize_t backlight_show_power(struct device *dev,
-		struct device_attribute *attr,char *buf)
+		struct device_attribute *attr, char *buf)
 {
 	struct backlight_device *bd = to_backlight_device(dev);
 
@@ -116,7 +116,7 @@
 	struct backlight_device *bd = to_backlight_device(dev);
 	unsigned long power;
 
-	rc = strict_strtoul(buf, 0, &power);
+	rc = kstrtoul(buf, 0, &power);
 	if (rc)
 		return rc;
 
@@ -150,7 +150,7 @@
 	struct backlight_device *bd = to_backlight_device(dev);
 	unsigned long brightness;
 
-	rc = strict_strtoul(buf, 0, &brightness);
+	rc = kstrtoul(buf, 0, &brightness);
 	if (rc)
 		return rc;