The crypto API's support for alignmasks for ahash algorithms is nearly
useless, as its only effect is to cause the API to align the key and
result buffers.  The drivers that happen to be specifying an alignmask
for ahash rarely actually need it.  When they do, it's easily fixable,
especially considering that these buffers cannot be used for DMA.

In preparation for removing alignmask support from ahash, this patch
makes the artpec6 driver no longer use it.  This driver is unusual in
that it DMAs the digest directly to the result buffer.  This is broken
because the crypto API provides the result buffer as an arbitrary
virtual address, which might not be valid for DMA, even after the crypto
API applies the alignmask.  Maybe the alignmask (which this driver set
only to 3) made this code work in a few more cases than it otherwise
would have.  But even if so, it doesn't make sense for this single
driver that is broken anyway to block removal of the alignmask support.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>