radeonsi/gfx11: mark streamout as unimplemented for now

Acked-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/16328>

src/gallium/drivers/radeonsi/si_state_shaders.cpp

@@ -3098,6 +3098,11 @@ static void *si_create_shader_selector(struct pipe_context *ctx,
    if (!sel)
       return NULL;
 
+   if (sscreen->info.chip_class == GFX11 && state->stream_output.num_outputs) {
+      fprintf(stderr, "radeonsi: streamout unimplemented\n");
+      abort();
+   }
+
    sel->screen = sscreen;
    sel->compiler_ctx_state.debug = sctx->debug;
    sel->compiler_ctx_state.is_debug_context = sctx->is_debug;