scsi: core: Add a no_highmem flag to struct Scsi_Host

scsi: core: Add a no_highmem flag to struct Scsi_Host

While we really should be killing the block layer bounce buffering ASAP, I
even more urgently need to stop the drivers to fiddle with the limits from
->slave_configure.  Add a no_highmem flag to the Scsi_Host to centralize
this setting and switch the remaining four drivers that use block layer
bounce buffering to it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240409143748.980206-7-hch@lst.de
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>