update docs

Author: hathach

README.rst

@@ -20,8 +20,8 @@ Please take a look at the online `documentation <https://docs.tinyusb.org/>`__.
 	├── docs            # Documentation
 	├── examples        # Sample with Makefile build support
 	├── hw
-	│   ├── bsp         # Supported boards source files
-	│   └── mcu         # Low level mcu core & peripheral drivers
+	│   ├── bsp         # Supported boards source files
+	│   └── mcu         # Low level mcu core & peripheral drivers
 	├── lib             # Sources from 3rd party such as freeRTOS, fatfs ...
 	├── src             # All sources files for TinyUSB stack itself.
 	├── test            # Unit tests for the stack
@@ -89,6 +89,13 @@ Host Stack
 - Mass Storage Class (MSC)
 - Hub with multiple-level support
 
+TypeC PD Stack
+==============
+
+- Power Delivery 3.0 (PD3.0) with USB Type-C support (WIP)
+- Super early stage, only for testing purpose
+- Only support STM32 G4
+
 OS Abstraction layer
 ====================