Re-export more `rustc_span::symbol` things from `rustc_span`.

`rustc_span::symbol` defines some things that are re-exported from
`rustc_span`, such as `Symbol` and `sym`. But it doesn't re-export some
closely related things such as `Ident` and `kw`. So you can do `use
rustc_span::{Symbol, sym}` but you have to do `use
rustc_span::symbol::{Ident, kw}`, which is inconsistent for no good
reason.

This commit re-exports `Ident`, `kw`, and `MacroRulesNormalizedIdent`,
and changes many `rustc_span::symbol::` qualifiers in `compiler/` to
`rustc_span::`. This is a 200+ net line of code reduction, mostly
because many files with two `use rustc_span` items can be reduced to
one.

1 files changed, 2 insertions, 3 deletions

diff --git a/compiler/rustc_builtin_macros/src/autodiff.rs b/compiler/rustc_builtin_macros/src/autodiff.rs
index 66bb11ca522..8960cf6ab59 100644
--- a/compiler/rustc_builtin_macros/src/autodiff.rs
+++ b/compiler/rustc_builtin_macros/src/autodiff.rs
@@ -20,8 +20,7 @@ mod llvm_enzyme {
         PatKind, TyKind,
     };
     use rustc_expand::base::{Annotatable, ExtCtxt};
-    use rustc_span::symbol::{Ident, kw, sym};
-    use rustc_span::{Span, Symbol};
+    use rustc_span::{Ident, Span, Symbol, kw, sym};
     use thin_vec::{ThinVec, thin_vec};
     use tracing::{debug, trace};
 
@@ -35,7 +34,7 @@ mod llvm_enzyme {
             FnRetTy::Default(_) => false,
         }
     }
-    fn first_ident(x: &MetaItemInner) -> rustc_span::symbol::Ident {
+    fn first_ident(x: &MetaItemInner) -> rustc_span::Ident {
         let segments = &x.meta_item().unwrap().path.segments;
         assert!(segments.len() == 1);
         segments[0].ident