ac/nir: clamp vertex color outputs in the right place

Reviewed-by: Timur Kristóf <timur.kristof@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/32910>

src/amd/common/nir/ac_nir_lower_legacy_vs.c

@@ -70,6 +70,9 @@ ac_nir_lower_legacy_vs(nir_shader *nir,
    /* This should be after streamout and before exports. */
    ac_nir_clamp_vertex_color_outputs(&b, &out);
 
+   /* This should be after streamout and before exports. */
+   ac_nir_clamp_vertex_color_outputs(&b, &out);
+
    uint64_t export_outputs = nir->info.outputs_written | VARYING_BIT_POS;
    if (kill_pointsize)
       export_outputs &= ~VARYING_BIT_PSIZ;