greybus: connection: remove CDSI1 hack

This hack is not necessary anymore since the firmware is now able to
handle correctly (dis)connect{ed,ing} operations on the CDSI CPort.

Testing Done: Checked that I could start the camera app several time
              and got the preview each time.

Signed-off-by: Fabien Parent <fparent@baylibre.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@linaro.org>
Reviewed-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Alex Elder <elder@linaro.org>