Adapt ssl_clear_peer_cert() to removal of `peer_cert` field
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index 40d5975..fff5e9d 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -6189,14 +6189,14 @@
 
 static void ssl_clear_peer_cert( mbedtls_ssl_session *session )
 {
+#if defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
     if( session->peer_cert != NULL )
     {
         mbedtls_x509_crt_free( session->peer_cert );
         mbedtls_free( session->peer_cert );
         session->peer_cert = NULL;
     }
-
-#if !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
+#else
     if( session->peer_cert_digest != NULL )
     {
         /* Zeroization is not necessary. */
@@ -6205,7 +6205,7 @@
         session->peer_cert_digest_type = MBEDTLS_MD_NONE;
         session->peer_cert_digest_len  = 0;
     }
-#endif /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
+#endif /* !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
 }
 
 /*