media: atomisp: remove unused hmm address translation functions

hmm_isp_vaddr_to_host_vaddr() and hmm_host_vaddr_to_hrt_vaddr()
are unused, remove them.

Link: https://lore.kernel.org/linux-media/20220615205037.16549-28-hdegoede@redhat.com


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>