Wasteful formatting of type family with injectivity constraint

Given this input:
```
type family Foo (cv :: Bar)
    = result | result -> cv where
  Foo '[] = Baz
```

ormolu (built at 9dbba53) produces this output:
```
type family
  Foo (cv :: Bar) =
    result
    | result -> cv where
  Foo '[] = Baz
```

4 lines seems excessive for this.

FYI, @judah