Update changelogs

Author: kellda

tm4c-hal/README.md

@@ -9,7 +9,7 @@ depending on your processor.
 
 ### Unreleased Changes ([Source](https://github.com/rust-embedded-community/tm4c-hal/tree/master/tm4c-hal) [Diff](https://github.com/rust-embedded-community/tm4c-hal/compare/tm4c-hal-0.4.1...master))
 
-* No changes
+* Implement use of sealed traits by downstream crates (i.e. `tm4c123x-hal` and `tm4c129x-hal`)
 
 ### v0.4.1 ([Source](https://github.com/rust-embedded-community/tm4c-hal/tree/tm4c-hal-0.4.1/tm4c-hal) [Diff](https://github.com/rust-embedded-community/tm4c-hal/compare/tm4c-hal-0.4.1...tm4c-hal-0.4.0))
 

tm4c123x-hal/README.md

@@ -10,7 +10,8 @@
 
 ### Unreleased Changes ([Source](https://github.com/rust-embedded-community/tm4c-hal/tree/master/tm4c123x-hal) [Diff](https://github.com/rust-embedded-community/tm4c-hal/compare/tm4c123x-hal-0.10.2...master))
 
-* No changes
+* Use sealed traits for `*Pin` marker traits
+* Do not reexport `tm4c-hal` macros
 
 ### v0.10.2 ([Source](https://github.com/rust-embedded-community/tm4c-hal/tree/tm4c123x-hal-0.10.2/tm4c123x-hal) [Diff](https://github.com/rust-embedded-community/tm4c-hal/compare/tm4c123x-hal-0.10.2...tm4c123x-hal-0.10.1))
 

tm4c129x-hal/README.md

@@ -10,7 +10,8 @@
 
 ### Unreleased Changes ([Source](https://github.com/rust-embedded-community/tm4c-hal/tree/master/tm4c129x-hal) [Diff](https://github.com/rust-embedded-community/tm4c-hal/compare/tm4c129x-hal-0.9.2...master))
 
-* No changes
+* Use sealed traits for `*Pin` marker traits
+* Do not reexport `tm4c-hal` macros
 
 ### v0.9.2 ([Source](https://github.com/rust-embedded-community/tm4c-hal/tree/tm4c129x-hal-0.9.2/tm4c129x-hal) [Diff](https://github.com/rust-embedded-community/tm4c-hal/compare/tm4c129x-hal-0.9.2...tm4c129x-hal-0.9.1))