Remove ast:: & base:: prefixes from some builtin macros

compiler/rustc_builtin_macros/src/compile_error.rs

@@ -1,14 +1,14 @@
 // The compiler code necessary to support the compile_error! extension.
 
 use rustc_ast::tokenstream::TokenStream;
-use rustc_expand::base::{self, *};
+use rustc_expand::base::{get_single_str_from_tts, DummyResult, ExtCtxt, MacResult};
 use rustc_span::Span;
 
 pub fn expand_compile_error<'cx>(
     cx: &'cx mut ExtCtxt<'_>,
     sp: Span,
     tts: TokenStream,
-) -> Box<dyn base::MacResult + 'cx> {
+) -> Box<dyn MacResult + 'cx> {
     let var = match get_single_str_from_tts(cx, sp, tts, "compile_error!") {
         Ok(var) => var,
         Err(guar) => return DummyResult::any(sp, guar),