media: atomisp: prevent integer overflow in sh_css_set_black_frame()

The "height" and "width" values come from the user so the "height * width"
multiplication can overflow.

Link: https://lore.kernel.org/r/YxBBCRnm3mmvaiuR@kili



Fixes: a49d2536 ("staging/atomisp: Add support for the Intel IPU v2")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>