Replace hash_info_get_type with MD function

Mostly a search and replace with just two manual changes:

1. Now PK and TLS need MD light, so auto-enable it.
2. Remove the old function in hash_info.[ch]

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
diff --git a/library/ssl_tls12_client.c b/library/ssl_tls12_client.c
index 691fa62..b875fac 100644
--- a/library/ssl_tls12_client.c
+++ b/library/ssl_tls12_client.c
@@ -2408,7 +2408,7 @@
             mbedtls_pk_rsassa_pss_options rsassa_pss_options;
             rsassa_pss_options.mgf1_hash_id = md_alg;
             rsassa_pss_options.expected_salt_len =
-                mbedtls_hash_info_get_size(md_alg);
+                mbedtls_md_get_size_from_type(md_alg);
             if (rsassa_pss_options.expected_salt_len == 0) {
                 return MBEDTLS_ERR_SSL_INTERNAL_ERROR;
             }