drivers/block: Remove PARIDE core and high-level protocols

Remove PARIDE core and high level protocols, taking care not to break
low-level drivers (used by pata_parport). Also update documentation.

Signed-off-by: Ondrej Zary <linux@zary.sk>
Acked-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>