crypto: hisilicon/sec - fix auth key size error

The authentication algorithm supports a maximum of 128-byte keys.
The allocated key memory is insufficient.

Fixes: 2f072d75 ("crypto: hisilicon - Add aead support on SEC2")
Signed-off-by: Kai Ye <yekai13@huawei.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>