crypto: caam - Remove broken arc4 support

crypto: caam - Remove broken arc4 support

The arc4 algorithm requires storing state in the request context
in order to allow more than one encrypt/decrypt operation.  As this
driver does not seem to do that, it means that using it for more
than one operation is broken.

Fixes: eaed71a44ad9 ("crypto: caam - add ecb(*) support")
Link: https://lore.kernel.org/linux-crypto/CAMj1kXGvMe_A_iQ43Pmygg9xaAM-RLy=_M=v+eg--8xNmv9P+w@mail.gmail.com
Link: https://lore.kernel.org/linux-crypto/20200702101947.682-1-ardb@kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>