crypto: fix crc64 testmgr digest byte order

The result is set in little endian, so the expected digest needs to
be consistent for big endian machines.

Fixes: f3813f4b ("crypto: add rocksoft 64b crc guard tag framework")
Reported-by: Vasily Gorbik <gor@linux.ibm.com>
Reported-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20220322142107.4581-1-kbusch@kernel.org


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