Spellchecking some comments

This PR attempts to clean up some minor spelling mistakes in comments

compiler/rustc_builtin_macros/src/cfg_eval.rs

@@ -137,7 +137,7 @@ impl CfgEval<'_, '_> {
         }
 
         // The majority of parsed attribute targets will never need to have early cfg-expansion
-        // run (e.g. they are not part of a `#[derive]` or `#[cfg_eval]` macro inoput).
+        // run (e.g. they are not part of a `#[derive]` or `#[cfg_eval]` macro input).
         // Therefore, we normally do not capture the necessary information about `#[cfg]`
         // and `#[cfg_attr]` attributes during parsing.
         //

compiler/rustc_builtin_macros/src/deriving/clone.rs

@@ -28,7 +28,7 @@ pub fn expand_deriving_clone(
     // - the item is a union with Copy fields
     //      Unions with generic parameters still can derive Clone because they require Copy
     //      for deriving, Clone alone is not enough.
-    //      Whever Clone is implemented for fields is irrelevant so we don't assert it.
+    //      Wherever Clone is implemented for fields is irrelevant so we don't assert it.
     let bounds;
     let substructure;
     let is_shallow;

compiler/rustc_builtin_macros/src/edition_panic.rs

@@ -70,7 +70,7 @@ fn expand<'cx>(
 }
 
 pub fn use_panic_2021(mut span: Span) -> bool {
-    // To determine the editon, we check the first span up the expansion
+    // To determine the edition, we check the first span up the expansion
     // stack that does not have #[allow_internal_unstable(edition_panic)].
     // (To avoid using the edition of e.g. the assert!() or debug_assert!() definition.)
     loop {