atomic queue limits updates v3

[Christoph Hellwig]

On Wed, Jan 31, 2024 at 06:26:49PM -0500, Martin K. Petersen wrote:
> Looks nice in general and avoids the annoyances I had with my discovery
> series wrt. discard. I'm in the process of rebasing that series to fit
> on top of your changes and things get cleaned up nicely. We'll probably
> have to coordinate the sd changes a bit.

FYI, I haven't really started on SCSI for a bit of protoyping, and it
will take a while to get to it.