aes/asm/aesv8-armx.pl: optimize for Cortex-A5x.

ARM has optimized Cortex-A5x pipeline to favour pairs of complementary
AES instructions. While modified code improves performance of post-r0p0
Cortex-A53 performance by >40% (for CBC decrypt and CTR), it hurts
original r0p0. We favour later revisions, because one can't prevent
future from coming. Improvement on post-r0p0 Cortex-A57 exceeds 50%,
while new code is not slower on r0p0, or Apple A7 for that matter.

[Update even SHA results for latest Cortex-A53.]

Reviewed-by: Richard Levitte <levitte@openssl.org>