nir/prog: Use nir_foreach_variable

Reviewed-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Iago Toral Quiroga <itoral@igalia.com>

src/mesa/program/prog_to_nir.c

@@ -923,7 +923,7 @@ ptn_add_output_stores(struct ptn_compile *c)
 {
    nir_builder *b = &c->build;
 
-   foreach_list_typed(nir_variable, var, node, &b->shader->outputs) {
+   nir_foreach_variable(var, &b->shader->outputs) {
       nir_intrinsic_instr *store =
          nir_intrinsic_instr_create(b->shader, nir_intrinsic_store_var);
       store->num_components = glsl_get_vector_elements(var->type);