greybus: es2: implement cport reset control request

Toshiba UniPro IP requires to reset the CPort that has been used in a previous
connection. This commit implement a new control request in order to
reset CPorts on an APBridgeA.

Signed-off-by: Fabien Parent <fparent@baylibre.com>
Reviewed-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>