In preparation for optimizing the CCM core asm code using permutation
vectors and overlapping loads and stores, ensure that inputs shorter
than the size of a AES block are passed via a buffer on the stack, in a
way that positions the data at the end of a 16 byte buffer. This removes
the need for the asm code to reason about a rare corner case where the
tail of the data cannot be read/written using a single NEON load/store
instruction.

While at it, tweak the copyright header and authorship to bring it up to
date.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>