ac/nir: remove no-op loop from ac_nir_create_gs_copy_shader

Reviewed-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@amd.com>
Reviewed-by: Timur Kristóf <timur.kristof@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/35352>

src/amd/common/nir/ac_nir_create_gs_copy_shader.c

@@ -27,9 +27,6 @@ ac_nir_create_gs_copy_shader(const nir_shader *gs_nir,
    nir_builder b = nir_builder_init_simple_shader(
       MESA_SHADER_VERTEX, gs_nir->options, "gs_copy");
 
-   nir_foreach_shader_out_variable(var, gs_nir)
-      nir_shader_add_variable(b.shader, nir_variable_clone(var, b.shader));
-
    b.shader->info.outputs_written = gs_nir->info.outputs_written;
    b.shader->info.outputs_written_16bit = gs_nir->info.outputs_written_16bit;