Fix `foreign export` #294

examples/demo/demo.odin

@@ -836,8 +836,14 @@ diverging_procedures :: proc() {
 	foo();
 }
 
+foreign export {
+	bar :: proc "c" () -> i32 {
+		return 123;
+	}
+}
+
 main :: proc() {
-	when true {
+	when false {
 		general_stuff();
 		union_type();
 		parametric_polymorphism();

src/ir.cpp

@@ -9744,6 +9744,7 @@ void ir_gen_tree(irGen *s) {
 			irValue *p = ir_value_procedure(m, e, e->type, type_expr, body, name);
 			p->Proc.tags = pl->tags;
 			p->Proc.inlining = pl->inlining;
+			p->Proc.is_export = e->Procedure.is_export;
 
 			ir_module_add_value(m, e, p);
 			HashKey hash_name = hash_string(name);