s390/mm: remove unused cmma functions

The last user of arch_set_page_states(), arch_set_page_nodat() and
arch_test_page_nodat() was removed in commit 39421627
("s390: remove broken hibernate / power management support"),
let's remove these functions.

Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20210806075430.6103-1-david@redhat.com


Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>