Fix 'LICENSE' file 404 link error

Author: mrcoulter45

README.md

@@ -1,8 +1,8 @@
 [![Mbed OS][mbed-os-logo]][mbed-os-link]
 
-[![Build status release][mbed-travis-release-svg]][mbed-travis-release] 
-[![Build status master][mbed-travis-master-svg]][mbed-travis-master] 
-[![Tools coverage status][mbed-coveralls-tools-svg]][mbed-coveralls-tools] 
+[![Build status release][mbed-travis-release-svg]][mbed-travis-release]
+[![Build status master][mbed-travis-master-svg]][mbed-travis-master]
+[![Tools coverage status][mbed-coveralls-tools-svg]][mbed-coveralls-tools]
 
 [mbed-os-logo]: logo.png
 [mbed-os-link]: https://www.mbed.com/en/platform/mbed-os/
@@ -19,25 +19,25 @@ Mbed OS provides a platform that includes:
 
 - Security foundations.
 - Cloud management services.
-- Drivers for sensors, I/O devices and connectivity. 
+- Drivers for sensors, I/O devices and connectivity.
 
 ## Release notes
 The [release notes](https://os.mbed.com/releases) detail the current release. You can also find information about previous versions.
 
-## License and contributions 
+## License and contributions
 
 The software is provided under the [Apache-2.0 license](LICENSE-apache-2.0.txt). Contributions to this project are accepted under the same license. Please see [contributing.md](CONTRIBUTING.md) for more information.
 
 This project contains code from other projects. The original license text is included in those source files. They must comply with our [license guide](https://os.mbed.com/docs/mbed-os/latest/contributing/license.html).
 
-Folders containing files under different permissive license than Apache 2.0 are listed in the [LICENSE](LICENSE) file.
+Folders containing files under different permissive license than Apache 2.0 are listed in the [LICENSE](LICENSE.md) file.
 
 ## Getting started for developers
- 
+
 We have a [developer website](https://os.mbed.com) for asking questions, engaging with others, finding information on boards and components, using an online IDE and compiler, reading the documentation and learning about what's new and what's coming next in Mbed OS.
 
 ## Getting started for contributors
- 
+
 We also have a [contributing and publishing guide](https://os.mbed.com/contributing/) that covers licensing, contributor agreements and style guidelines.
 
 ## Documentation