block: remove last remaining traces of IDE documentation

The last traces of the IDE driver went away in commit b7fb14d3
("ide: remove the legacy ide driver") but it left behind some traces
of old documentation.

As luck would have it Randy and I would submit similar changes within
a week of each other to address this.  As Randy's commit is in the doc
tree already - this delta is just the stuff my removal contained that
was not in Randy's IDE doc removal.

Cc: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Phillip Potter <phil@philpotter.co.uk>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Link: https://lore.kernel.org/all/20220427165917.GE12977@windriver.com


[phil@philpotter.co.uk: removed diffs already added by others]
Signed-off-by: Phillip Potter <phil@philpotter.co.uk>
Link: https://lore.kernel.org/r/20220515205833.944139-5-phil@philpotter.co.uk


Signed-off-by: Jens Axboe <axboe@kernel.dk>