Fix issue with printing invalid IR for nested unions

(GitHub #4)

code/demo.odin

@@ -1,6 +1,14 @@
-#import "fmt.odin";
-#import "sync.odin";
+Test1 :: type union {
+	A: int;
+	B: int;
+};
+
+Test :: type struct {
+	a: Test1;
+};
 
 main :: proc() {
-	fmt.println("Hellope");
-}
+	test: Test;
+	match type x : ^test.a {
+	}
+};