Rollup merge of rust-lang#141603 - nnethercote:reduce-P, r=fee1-dead

Reduce `ast::ptr::P` to a typedef of `Box`

As per the MCP at rust-lang/compiler-team#878.

r? `@fee1-dead`

Author: GuillaumeGomez

clippy_lints/src/unnested_or_patterns.rs

@@ -426,7 +426,7 @@ fn drain_matching(
         // Check if we should extract, but only if `idx >= start`.
         if idx > start && predicate(&alternatives[i].kind) {
             let pat = alternatives.remove(i);
-            tail_or.push(extract(pat.into_inner().kind));
+            tail_or.push(extract(pat.kind));
         } else {
             i += 1;
         }