Use the key-matrix layer to interpret key scan information from the EC
and inject input based on the FDT-supplied key map. This driver registers
itself with the ChromeOS EC driver to perform communications.

The matrix-keypad FDT binding is used with a small addition to control
ghosting.
Signed-off-by: NSimon Glass <sjg@chromium.org>
Signed-off-by: NLuigi Semenzato <semenzato@chromium.org>
Signed-off-by: NVincent Palatin <vpalatin@chromium.org>
Acked-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>