Now that a single build supports both the ISP 2400 and the ISP 2401
this function is no longer necessary. The main probe() already
contains a similar switch (id->device & ATOMISP_PCI_DEVICE_SOC_MASK)
checking for a known device_id.
Move the revision check into the main probe() and drop
the is_valid_device() function.
Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>