crypto: ccree - convert to use crypto_authenc_extractkeys()

Convert the ccree crypto driver to use crypto_authenc_extractkeys() so
that it picks up the fix for broken validation of rtattr::rta_len.

Fixes: ff27e85a

 ("crypto: ccree - add AEAD support")
Cc: <stable@vger.kernel.org> # v4.17+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>