router: ignore clippy lint missing_transmute_annotations

the `ApiHandler`'s `PartialEq` implementation makes heavy use of
`transmute`. clippy wants the types to be explicitly stated here and
not inferred, to avoid potential undefined behaviour if an unexpected
type is inferred. however, the types that would be inferred here are
so complex, that the code would become illegible anyway, so ignore
this lint for now.

[1]:
https://rust-lang.github.io/rust-clippy/master/index.html#missing_transmute_annotations

Signed-off-by: Shannon Sterz <s.sterz@proxmox.com>

proxmox-router/src/router.rs

@@ -495,6 +495,7 @@ impl Eq for ApiHandler {}
 impl PartialEq for ApiHandler {
     fn eq(&self, rhs: &Self) -> bool {
         unsafe {
+            #[allow(clippy::missing_transmute_annotations)]
             match (self, rhs) {
                 (ApiHandler::Sync(l), ApiHandler::Sync(r)) => {
                     core::mem::transmute::<_, usize>(l) == core::mem::transmute::<_, usize>(r)