This renames the hdlc_lite module to just HDLC to accommodate for future
development.
Change-Id: Ic96502a9f41d3a10179435347d4e8615bc3ae844
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/29042
Reviewed-by: Keir Mierle <keir@google.com>
Reviewed-by: Wyatt Hepler <hepler@google.com>