Changes from #88558 allowed using `~const Drop` in constants by
introducing a new `NeedsNonConstDrop` qualif.
The new qualif was also used for promotion purposes, and allowed
promotion to happen for values that needs to be dropped but which
do have a const drop impl.
Since for promoted the drop implementation is never executed,
this lead to observable change in behaviour. For example:
```rust
struct Panic();
impl const Drop for Panic {
fn drop(&mut self) {
panic!();
}
}
fn main() {
let _ = &Panic();
}
```
Restore the use of `NeedsDrop` qualif during promotion to avoid the issue.
915a581bcb