i40iw: Replace the obsolete crypto hash interface with shash

This patch replaces the obsolete crypto hash interface with shash
and resolves a build failure after merge of the rdma tree
which is caused by the removal of crypto hash interface

Removing CRYPTO_ALG_ASYNC from crypto_alloc_shash(),
because it is by definition sync only

Signed-off-by: Mustafa Ismail <mustafa.ismail@intel.com>
Signed-off-by: Tatyana Nikolova <tatyana.e.nikolova@intel.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Doug Ledford <dledford@redhat.com>