If we fail to queue the buffer then it can never be dequeued.  This can
lead to a forever loop in stop_streaming() when we wait for everything
to finish.

Fixes: 70ec64cc ("staging: bcm2835-camera: Ensure all buffers are returned on disable")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20200722130651.GC220681@mwandaSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>