tls-crypto: Filter TLS cipher suites by min/max version

There is no point proposing legacy (or future) cipher suites depending on
the proposed TLS versions. It was actually possible to negotiate and use
cipher suites only defined for TLS 1.2 with earlier TLS versions.

src/libtls/tls_crypto.h

@@ -615,9 +615,11 @@ tls_crypto_t *tls_crypto_create(tls_t *tls, tls_cache_t *cache);
  * Get a list of all supported TLS cipher suites.
  *
  * @param null			include supported NULL encryption suites
+ * @param version		TLS version
  * @param suites		pointer to allocated suites array, to free(), or NULL
  * @return				number of suites supported
  */
-int tls_crypto_get_supported_suites(bool null, tls_cipher_suite_t **suites);
+int tls_crypto_get_supported_suites(bool null, tls_version_t version,
+									tls_cipher_suite_t **suites);
 
 #endif /** TLS_CRYPTO_H_ @}*/