doc: remove the redundant Fixed: from the Fixed section's items

Author: yvt

CHANGELOG.md

@@ -13,8 +13,8 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 ### Fixed
 
-- Fixed: Wrap const generic arguments in braces, fixing builds on the latest compiler version
-- Fixed: Remove `#[naked]` when inlining is prerequisite for correctness; functions with `#[naked]` are no longer eligible for inlining as of [rust-lang/rust#79192](https://github.com/rust-lang/rust/pull/79192).
+- Wrap const generic arguments in braces, fixing builds on the latest compiler version
+- Remove `#[naked]` when inlining is prerequisite for correctness; functions with `#[naked]` are no longer eligible for inlining as of [rust-lang/rust#79192](https://github.com/rust-lang/rust/pull/79192).
 
 ## 0.1.0 - 2020-11-03