crypto: engine - Realign struct crypto_engine to save 8 bytes

Realign struct crypto_engine to reduce its size by 8 bytes. Total size
is now 192 bytes, allowing it to fit within 3 cachelines instead of 4.

pahole output before:

  /* size: 200, cachelines: 4, members: 17 */
  /* sum members: 183, holes: 3, sum holes: 17 */
  /* paddings: 1, sum paddings: 4 */
  /* last cacheline: 8 bytes */

and after:

  /* size: 192, cachelines: 3, members: 17 */
  /* sum members: 183, holes: 2, sum holes: 9 */
  /* paddings: 1, sum paddings: 4 */

No functional changes intended.

Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>