kernfs: Fix typo 'the the' in comment

Replace 'the the' with 'the' in the comment.
Signed-off-by: Slark Xiao <slark_xiao@163.com>
Link: https://lore.kernel.org/r/20220722100518.79741-1-slark_xiao@163.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

fs/kernfs/file.c

@@ -307,7 +307,7 @@ static ssize_t kernfs_fop_read_iter(struct kiocb *iocb, struct iov_iter *iter)
  * There is no easy way for us to know if userspace is only doing a partial
  * write, so we don't support them. We expect the entire buffer to come on
  * the first write.  Hint: if you're writing a value, first read the file,
- * modify only the the value you're changing, then write entire buffer
+ * modify only the value you're changing, then write entire buffer
  * back.
  */
 static ssize_t kernfs_fop_write_iter(struct kiocb *iocb, struct iov_iter *iter)