Add RSA-PSS key certificate type.

Recognise RSA-PSS certificate algorithm and add a new certificate
type.

Reviewed-by: Ben Kaduk <kaduk@mit.edu>
(Merged from https://github.com/openssl/openssl/pull/4368)
diff --git a/ssl/ssl_cert_table.h b/ssl/ssl_cert_table.h
index eae9ff2..fd6a1ad 100644
--- a/ssl/ssl_cert_table.h
+++ b/ssl/ssl_cert_table.h
@@ -12,6 +12,7 @@
  */
 static const SSL_CERT_LOOKUP ssl_cert_info [] = {
     {EVP_PKEY_RSA, SSL_aRSA}, /* SSL_PKEY_RSA */
+    {EVP_PKEY_RSA_PSS, SSL_aRSA}, /* SSL_PKEY_RSA_PSS_SIGN */
     {EVP_PKEY_DSA, SSL_aDSS}, /* SSL_PKEY_DSA_SIGN */
     {EVP_PKEY_EC, SSL_aECDSA}, /* SSL_PKEY_ECC */
     {NID_id_GostR3410_2001, SSL_aGOST01}, /* SSL_PKEY_GOST01 */