Fix false -Wodr warnings

[Dominique d'Humières]

Hi Jan,

The test causes

WARNING: lto.exp does not support dg-do
WARNING: lto.exp does not support dg-options in primary source file

This is fixed by the following patch

--- ../_clean/gcc/testsuite/g++.dg/lto/pr89358_0.C	2019-04-15 00:04:48.000000000 +0200
+++ gcc/testsuite/g++.dg/lto/pr89358_0.C	2019-04-16 13:13:14.000000000 +0200
@@ -1,5 +1,5 @@
-/* { dg-do link } */
-/* { dg-options "-std=c++17"  } */
+/* { dg-lto-do link } */
+/* { dg-lto-options "-std=c++17"  } */
 #include <map>
 
 extern void test();
--- ../_clean/gcc/testsuite/g++.dg/lto/pr89358_1.C	2019-04-15 00:04:48.000000000 +0200
+++ gcc/testsuite/g++.dg/lto/pr89358_1.C	2019-04-16 13:14:44.000000000 +0200
@@ -1,4 +1,3 @@
-/* { dg-options "-std=c++14"  } */
 #include <map>
 
 void test()

TIA

Dominique