media: atomisp: remove hmm_mem_stats

Without pool support the (optional) debug logging done by these is
not really meaningful, drop it all.

Link: https://lore.kernel.org/linux-media/20220615205037.16549-13-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>