media: atomisp: Remove unused css_pipe_id argument from atomisp_css_[start|stop]()

The css_pipe_id argument pass to atomisp_css_[start|stop]() is
not used, drop it.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>