tests/qtest: Use EXIT_FAILURE instead of magic number

When migration fails, QEMU exits with a status code EXIT_FAILURE.
Change qtests to use the well-defined macro instead of magic number.

Signed-off-by: Bin Meng <bin.meng@windriver.com>
Message-Id: <20221028045736.679903-6-bin.meng@windriver.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>

tests/qtest/dbus-vmstate-test.c

@@ -233,7 +233,7 @@ test_dbus_vmstate(Test *test)
     test->src_qemu = src_qemu;
     if (test->migrate_fail) {
         wait_for_migration_fail(src_qemu, true);
-        qtest_set_expected_status(dst_qemu, 1);
+        qtest_set_expected_status(dst_qemu, EXIT_FAILURE);
     } else {
         wait_for_migration_complete(src_qemu);
     }

tests/qtest/migration-test.c

@@ -1342,7 +1342,7 @@ static void test_precopy_common(MigrateCommon *args)
         wait_for_migration_fail(from, allow_active);
 
         if (args->result == MIG_TEST_FAIL_DEST_QUIT_ERR) {
-            qtest_set_expected_status(to, 1);
+            qtest_set_expected_status(to, EXIT_FAILURE);
         }
     } else {
         if (args->iterations) {
@@ -1738,7 +1738,7 @@ static void do_test_validate_uuid(MigrateStart *args, bool should_fail)
     migrate_qmp(from, uri, "{}");
 
     if (should_fail) {
-        qtest_set_expected_status(to, 1);
+        qtest_set_expected_status(to, EXIT_FAILURE);
         wait_for_migration_fail(from, true);
     } else {
         wait_for_migration_complete(from);