tls13: server: Select preferred cipher suite

Signed-off-by: Ronald Cron <ronald.cron@arm.com>
diff --git a/library/ssl_tls13_server.c b/library/ssl_tls13_server.c
index f557d7f..8aff191 100644
--- a/library/ssl_tls13_server.c
+++ b/library/ssl_tls13_server.c
@@ -1383,6 +1383,7 @@
         MBEDTLS_SSL_DEBUG_MSG(2, ("selected ciphersuite: %04x - %s",
                                   cipher_suite,
                                   ciphersuite_info->name));
+        break;
     }
 
     if (handshake->ciphersuite_info == NULL) {
@@ -1390,6 +1391,7 @@
                                      MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE);
         return MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE;
     }
+    p = cipher_suites_end;
 
     /* ...
      * opaque legacy_compression_methods<1..2^8-1>;