crypto: morus - remove generic and x86 implementations

MORUS was not selected as a winner in the CAESAR competition, which
is not surprising since it is considered to be cryptographically
broken [0]. (Note that this is not an implementation defect, but a
flaw in the underlying algorithm). Since it is unlikely to be in use
currently, let's remove it before we're stuck with it.

[0] https://eprint.iacr.org/2019/172.pdf

Reviewed-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto/testmgr.c

@@ -4768,18 +4768,6 @@ static const struct alg_test_desc alg_test_descs[] = {
 		.suite = {
 			.hash = __VECS(michael_mic_tv_template)
 		}
-	}, {
-		.alg = "morus1280",
-		.test = alg_test_aead,
-		.suite = {
-			.aead = __VECS(morus1280_tv_template)
-		}
-	}, {
-		.alg = "morus640",
-		.test = alg_test_aead,
-		.suite = {
-			.aead = __VECS(morus640_tv_template)
-		}
 	}, {
 		.alg = "nhpoly1305",
 		.test = alg_test_hash,