scsi: core: sysfs: Remove comments that conflict with the actual logic

Christoph Hellwig Says:
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I think we should just handle the error properly and remove the comment.
There's no good reason to ignore bsg registration errors.

In fact, after commit 92c4b58b ("scsi: core: Register sysfs attributes
earlier"), we are already forced to return errno.

We discuss this issue in [1].

[1] https://lore.kernel.org/all/20211022010201.426746-1-liu.yun@linux.dev/

Link: https://lore.kernel.org/r/20220329021251.123805-1-liu.yun@linux.dev


Suggested-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jackie Liu <liuyun01@kylinos.cn>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>