mm: move init_mem_debugging_and_hardening() to mm/mm_init.c

mm: move init_mem_debugging_and_hardening() to mm/mm_init.c

init_mem_debugging_and_hardening() is only called from mm_core_init().

Move it close to the caller, make it static and rename it to
mem_debugging_and_hardening_init() for consistency with surrounding
convention.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Mike Rapoport (IBM) <[email protected]>
Acked-by: David Hildenbrand <[email protected]>
Reviewed-by: Vlastimil Babka <[email protected]>
Cc: Doug Berger <[email protected]>
Cc: Matthew Wilcox (Oracle) <[email protected]>
Cc: Mel Gorman <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Thomas Bogendoerfer <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>