wl-shm: add support for more formats

src/it/test_gfx_api.rs

@@ -77,6 +77,7 @@ impl TestGfxCtx {
                             )
                         })
                         .collect(),
+                    supports_shm: true,
                 },
             );
         }

src/it/tests/t0001_shm_formats.rs

@@ -10,6 +10,7 @@ testcase!();
 
 /// Test that wl_shm supports the required formats
 async fn test(run: Rc<TestRun>) -> Result<(), TestError> {
+    run.backend.install_render_context(false)?;
     let client = run.create_client().await?;
     let formats = client.shm.formats().await;
     tassert!(formats.contains(&XRGB8888.wl_id.unwrap()));