The official Pine64 PinePhone keyboard case contains a matrix keypad and
a MCU which runs a libre firmware. Add support for its I2C interface.
Signed-off-by: Samuel Holland <samuel@sholland.org>
Link: https://lore.kernel.org/r/20220618165747.55709-3-samuel@sholland.orgSigned-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>