build: add test-gl-renderer option

This shall be used by CI due to https://gitlab.freedesktop.org/mesa/mesa/issues/2219

It defaults to true, meaning that people by default will be running the
GL-renderer tests. It works fine on hardware drivers, just not llvmpipe.

Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.com>

tests/weston-test-fixture-compositor.c

@@ -229,6 +229,13 @@ execute_compositor(const struct compositor_setup *setup,
 	}
 #endif
 
+#if !TEST_GL_RENDERER
+	if (setup->renderer == RENDERER_GL) {
+		fprintf(stderr, "GL-renderer disabled for tests, skipping.\n");
+		return RESULT_SKIP;
+	}
+#endif
+
 	prog_args_init(&args);
 
 	/* argv[0] */