The driver ftdi defines the command 'ftdi serial' to specify the serial string of the adapter. Remove and deprecate the driver command, and use 'adapter serial'. Change-Id: Ia5b1f325b9fab8f58b5ea70f8b807e50b148b939 Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com> Reviewed-on: https://review.openocd.org/c/openocd/+/6651 Tested-by: jenkins