fix units comment in encoder.hpp
fix units comment in encoder.hpp

madcowswe/ODrive,madcowswe/ODriveFirmware,madcowswe/ODrive,madcowswe/ODriveFirmware,madcowswe/ODriveFirmware,madcowswe/ODrive,madcowswe/ODrive,madcowswe/ODriveFirmware,madcowswe/ODrive