let_and_return suggestion causes errors macro_rule

[elichai]

Hi, the following code: https://play.rust-lang.org/?gist=0f26eb7594df37138a8ff964c50cc3ab
says the let binding is unnecessary but the suggestion causes the code to not compile with the following error:
error: attempted to repeat an expression containing no syntax variables matched as repeating at this depth

[JohnTitor]

Maybe we should not trigger this lint on macros.