crypto: x86/aegis128 - optimize length block preparation using SSE4.1

Start using SSE4.1 instructions in the AES-NI AEGIS code, with the first
use case being preparing the length block in fewer instructions.

In practice this does not reduce the set of CPUs on which the code can
run, because all Intel and AMD CPUs with AES-NI also have SSE4.1.

Upgrade the existing SSE2 feature check to SSE4.1, though it seems this
check is not strictly necessary; the aesni-intel module has been getting
away with using SSE4.1 despite checking for AES-NI only.

Reviewed-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>