Most SCSI drivers want to enable "clustering", that is merging of
segments so that they might span more than a single page. Remove the
ENABLE_CLUSTERING define, and require drivers to explicitly set
DISABLE_CLUSTERING to disable this feature.
Signed-off-by: Christoph Hellwig <email@example.com>
Signed-off-by: Martin K. Petersen <firstname.lastname@example.org>