block: remove a pointless self-reference in block_dev.c

There is no point in duplicating the file name in the top of the file
comment.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

fs/block_dev.c

 // SPDX-License-Identifier: GPL-2.0-only
 /*
- *  linux/fs/block_dev.c
- *
  *  Copyright (C) 1991, 1992  Linus Torvalds
  *  Copyright (C) 2001  Andrea Arcangeli <andrea@suse.de> SuSE
  */