feat(plat/st): add a USB DFU stack

Add a stack to support the Universal Serial Bus Device Class
Specification for Device Firmware Upgrade (USB DFU v1.1).

This stack is based on the USB device stack (USBD).

Change-Id: I8a56411d184882b6a9e3617c6dfb859086b8f353
Signed-off-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
2 files changed