crypto: Remove some unreachable algorithms

crypto: Remove some unreachable algorithms

The tls_ciphers table contained a number of algorithms that weren't
referenced in tls_cipher_suites. Remove those. That includes
TLS_CIPHER_IDEA_CBC, which was probably always broken because it was
mapped to CRYPTO_CIPHER_NULL. It also removes RC2, which is an
export-only cipher, despite the file saying it doesn't bother with
exportable ciphers.

That, in turn, removes all references to CRYPTO_CIPHER_ALG_RC2, so
remove that too. The OpenSSL port of CRYPTO_CIPHER_ALG_RC2 probably
never worked anyway because it uses RC2 in ECB mode instead of CBC.

It's likely other removals are possible. tlsv1_common.c has single-DES
ciphers, but tlsv1_client.c and tlsv1_server.c only configure a much
smaller list. There's also a lot of code for TLS_KEY_X_DH_anon, but
those ciphers aren't configured. I've left those alone because I'm not
sure how all this code is used.

Signed-off-by: David Benjamin <davidben@google.com>