Fix typo in comment

Author: jyn514

compiler/rustc_privacy/src/lib.rs

@@ -691,7 +691,7 @@ impl Visitor<'tcx> for EmbargoVisitor<'tcx> {
             hir::ItemKind::GlobalAsm(..) => {}
             hir::ItemKind::OpaqueTy(..) => {
                 // HACK(jynelson): trying to infer the type of `impl trait` breaks `async-std` (and `pub async fn` in general)
-                // Since rustdoc never need to do codegen and doesn't care about link-time reachability,
+                // Since rustdoc never needs to do codegen and doesn't care about link-time reachability,
                 // mark this as unreachable.
                 // See https://github.com/rust-lang/rust/issues/75100
                 if !self.tcx.sess.opts.actually_rustdoc {