Auto merge of rust-lang#140083 - ChrisDenton:rollup-o0xjy0y, r=ChrisDenton

Rollup of 5 pull requests

Successful merges:

 - rust-lang#138870 (Add target-specific NaN payloads for the missing tier 2 targets)
 - rust-lang#139028 (Make target maintainers more easily pingable)
 - rust-lang#140063 (Remove stray newline from post-merge report)
 - rust-lang#140067 (Remove (now unused) #[rustc_macro_edition_2021] attribute)
 - rust-lang#140068 (replace broken links armv7-rtems-eabihf.md)

r? `@ghost`
`@rustbot` modify labels: rollup

Author: bors

compiler/rustc_attr_data_structures/src/attributes.rs

@@ -191,7 +191,6 @@ pub enum AttributeKind {
     },
     MacroTransparency(Transparency),
     Repr(ThinVec<(ReprAttr, Span)>),
-    RustcMacroEdition2021,
     Stability {
         stability: Stability,
         /// Span of the `#[stable(...)]` or `#[unstable(...)]` attribute

compiler/rustc_attr_parsing/src/attributes/mod.rs

@@ -28,7 +28,6 @@ pub(crate) mod cfg;
 pub(crate) mod confusables;
 pub(crate) mod deprecation;
 pub(crate) mod repr;
-pub(crate) mod rustc;
 pub(crate) mod stability;
 pub(crate) mod transparency;
 pub(crate) mod util;