Update CHANGES for 11.3.0

CHANGES.md

@@ -3,6 +3,15 @@
 All notable changes to this project will be documented in this file.
 This project adheres to [Semantic Versioning](https://semver.org/).
 
+## 11.3.0 2021-04-21
+
+### Other changes
+* Added --depfile
+* Added --auto-sampled-textures
+* Now supports InterpolateAt-based functions
+* Supports cross-stage automatic IO mapping
+* Supports GL_EXT_vulkan_glsl_relaxed (-R option)
+
 ## 11.2.0 2021-02-18
 
 ### Other changes