Fix broken links in changelog

Author: TheZoq2

CHANGELOG.md

@@ -7,7 +7,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ## [Unreleased]
 
-## [0.7.0]
+## [v0.7.0]- 2020-10-17
 
 ### Breaking changes
 
@@ -235,7 +235,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 [Unreleased]: https://github.com/stm32-rs/stm32f1xx-hal/compare/v0.7.0...HEAD
 [v0.7.0]: https://github.com/stm32-rs/stm32f1xx-hal/compare/v0.6.1...v0.7.0
-[v0.6.0]: https://github.com/stm32-rs/stm32f1xx-hal/compare/v0.6.0...v0.6.1
+[v0.6.1]: https://github.com/stm32-rs/stm32f1xx-hal/compare/v0.6.0...v0.6.1
 [v0.6.0]: https://github.com/stm32-rs/stm32f1xx-hal/compare/v0.5.3...v0.6.0
 [v0.5.3]: https://github.com/stm32-rs/stm32f1xx-hal/compare/v0.5.2...v0.5.3
 [v0.5.2]: https://github.com/stm32-rs/stm32f1xx-hal/compare/v0.5.1...v0.5.2