Rollup merge of #104976 - WaffleLapkin:move_comments, r=cjgillot

Prefer doc comments over `//`-comments in compiler

Doc comments are generally nicer: they show up in the documentation, they are shown in IDEs when you hover other mentions of items, etc. Thus it makes sense to use them instead of `//`-comments.

compiler/rustc_lint/src/context.rs

@@ -206,7 +206,7 @@ impl LintStore {
         self.late_module_passes.push(Box::new(pass));
     }
 
-    // Helper method for register_early/late_pass
+    /// Helper method for register_early/late_pass
     pub fn register_lints(&mut self, lints: &[&'static Lint]) {
         for lint in lints {
             self.lints.push(lint);