pktcdvd: remove driver.

Way back in 2016 in commit 5a8b187c

 ("pktcdvd: mark as unmaintained
and deprecated") this driver was marked as "will be removed soon".  5
years seems long enough to have it stick around after that, so finally
remove the thing now.

Reported-by: Christoph Hellwig <hch@infradead.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Thomas Maier <balagi@justmail.de>
Cc: Peter Osterlund <petero2@telia.com>
Cc: linux-block@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20221202182758.1339039-1-gregkh@linuxfoundation.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>