As somewhat of a hack, allow flashing only the EC by deleting the
`firmware.rom` file before running `flash.sh`.
Signed-off-by: Tim Crawford <tcrawford@system76.com>
`flash.sh` was changed from internally flashing to using the UEFI
application (firmware-update). The option `--without-ec` was removed as
part of this.
Signed-off-by: Tim Crawford <tcrawford@system76.com>