undocument scsi_hba_attach() and ddi_dma_lim(9s)
These interfaces have been marked OBSOLETE for a long time. I'd like to undocument them, avoiding confusion in the man pages as part of an overall cleanup.
(The interfaces should also be formally removed, but that's out of scope for this change. To make that happen we have to be willing to risk breaking legacy binaries -- I think we can probably get away with that, but some investigation is needed first.)