cmd/compile: ICE when StructMake not lowered

```
package main

type Type struct {
	any
}

type typeObject struct {
	e struct{}
	b *byte
}

func f(b *byte) Type {
	return Type{
		typeObject{
			b: b,
		},
	}

}
```

Gives the error

```
tmp6.go:13:2: internal compiler error: 'f': not lowered: v12, StructMake STRUCT STRUCT PTR
```

This is a problem triggered by [CL 681937](https://go.dev/cl/681937).
