sysfs: sysfs_chmod_file's attr can be const

sysfs_chmod_file doesn't change the attribute it operates on, so this
attribute can be marked const.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

fs/sysfs/file.c

@@ -593,7 +593,8 @@ EXPORT_SYMBOL_GPL(sysfs_add_file_to_group);
  * @mode: file permissions.
  *
  */
-int sysfs_chmod_file(struct kobject *kobj, struct attribute *attr, mode_t mode)
+int sysfs_chmod_file(struct kobject *kobj, const struct attribute *attr,
+		     mode_t mode)
 {
 	struct sysfs_dirent *sd;
 	struct iattr newattrs;