Merge #19

19: Update USB story r=adamgreig a=Disasm

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## Category

Is this PR a:

- [ ] New Not Yet Awesome item?
- [x] A WIP project addressing an open item?
- [ ] Removing a Not Yet Awesome item?

## WIP Project checklist

- [x] Is there a link to the source project on GitHub/GitLab/etc?
- [x] Is the project open source?
- [ ] Is it clear if contributions are welcome?
- [x] Is the project relevant to the TODO item it addresses?
- [x] Is the project more than just an empty repo or a placeholder (e.g. just a "hello world" `bin.rs`/`lib.rs`)?

[Awesome Embedded Rust]: https://github.com/rust-embedded/awesome-embedded-rust


Co-authored-by: Vadim Kaushan <admin@disasm.info>

Author: bors[bot]

README.md

@@ -132,7 +132,14 @@ I'd like to be able to implement USB Host and USB Device support on the Texas In
 
 * The [tm4c123x-hal](https://crates.io/crates/tm4c123x-hal) crate has svd2rust definitions for the USB controller's registers.
 * There is a [branch](https://github.com/thejpster/tm4c-hal/tree/usb_host_support/tm4c123x-hal) looking at adding USB Host support.
-* [usb-device](https://github.com/mvirkkunen/usb-device) crate and corresponding device-specific implementation: [stm32f103xx-usb](https://github.com/mvirkkunen/stm32f103xx-usb).
+* [usb-device](https://github.com/mvirkkunen/usb-device) crate and corresponding device-specific implementations for STM32:
+  * [stm32-usbd](https://github.com/stm32-rs/stm32-usbd) (USBFS peripheral in F0, F1, F3, L0, L4 families)
+  * [synopsys-usb-otg](https://github.com/stm32-rs/synopsys-usb-otg) (OTG peripheral in F1, F4, F7, H7 families)
+* [usbd-serial](https://github.com/mvirkkunen/usbd-serial) crate implements USB CDC for serial communication.
+* [usbd-hid](https://github.com/twitchyliquid64/usbd-hid) crate implements USB HID, providing a way to implement
+keyboard and mouse drivers on top of it.
+* [Keyberon](https://github.com/TeXitoi/keyberon) project uses `usb-device` to implement its own HID support for USB keyboard firmware.
+This project usually serves as a starting point for those willing to implement their own USB keyboard firmware.
 
 ## Display and GUI support