* x86_64/aes-encrypt-internal.asm: Reduced unrolling. Keep state

in %eax--%edx only.
* x86_64/aes-decrypt-internal.asm: Likewise.

Rev: nettle/x86_64/aes-decrypt-internal.asm:1.3
Rev: nettle/x86_64/aes-encrypt-internal.asm:1.10