When the parent expression is not a predicate, translate `x != y` to:
```sql
CAST(x ^ y AS BIT)
```

instead of

```sql
CASE
    WHEN x <> y THEN CAST(1 AS bit)
    ELSE CAST(0 AS bit)
END
```

Similarly, translate `x == y` to:

```sql
CAST(x ^ y AS BIT) ^ CAST(1 AS bit)
```

instead of

```sql
CASE
    WHEN x == y THEN CAST(1 AS bit)
    ELSE CAST(0 AS bit)
END
```

Contributes to dotnet#34001.