Remove the `#[no_sanitize]` attribute in favor of `#[sanitize(xyz = "on|off")]`
This came up during the sanitizer stabilization (rust-lang/rust#123617). Instead of a `#[no_sanitize(xyz)]` attribute, we would like to have a `#[sanitize(xyz = "on|off")]` attribute, which is more powerful and allows to be extended in the future (instead
of just focusing on turning sanitizers off). The implementation is done according to what was [discussed on Zulip](https://rust-lang.zulipchat.com/#narrow/channel/343119-project-exploit-mitigations/topic/Stabilize.20the.20.60no_sanitize.60.20attribute/with/495377292)).
The new attribute also works on modules, traits and impl items and thus enables usage as the following:
```rust
#[sanitize(address = "off")]
mod foo {
fn unsanitized(..) {}
#[sanitize(address = "on")]
fn sanitized(..) {}
}
trait MyTrait {
#[sanitize(address = "off")]
fn unsanitized_default(..) {}
}
#[sanitize(thread = "off")]
impl MyTrait for () {
...
}
```
r? ```@rcvalle```
633cc0cc6c