Address review nitpicks.

Author: jumbatm

src/librustc_lint/context.rs

@@ -474,10 +474,10 @@ pub trait LintContext: Sized {
     fn sess(&self) -> &Session;
     fn lints(&self) -> &LintStore;
 
-    fn lookup_with_diagnostics<S: Into<MultiSpan>>(
+    fn lookup_with_diagnostics(
         &self,
         lint: &'static Lint,
-        span: Option<S>,
+        span: Option<impl Into<MultiSpan>>,
         decorate: impl for<'a> FnOnce(LintDiagnosticBuilder<'a>),
         diagnostic: BuiltinLintDiagnostics,
     ) {

src/librustc_lint/early.rs

@@ -41,11 +41,11 @@ impl<'a, T: EarlyLintPass> EarlyContextAndPass<'a, T> {
                 span,
                 msg,
                 node_id: _,
-                lint_id: _,
+                lint_id,
                 diagnostic,
             } = early_lint;
             self.context.lookup_with_diagnostics(
-                early_lint.lint_id.lint,
+                lint_id.lint,
                 Some(span),
                 |lint| lint.build(&msg).emit(),
                 diagnostic,