memblock: remove memblock_{set,clear}_region_flags

The memblock API provides dedicated helpers to set or clear a flag on a
memory region, e.g.  memblock_{mark,clear}_hotplug().

The memblock_{set,clear}_region_flags() functions are used only by the
memblock internal function that adjusts the region flags.  Drop these
functions and use open-coded implementation instead.

Link: http://lkml.kernel.org/r/1549455025-17706-2-git-send-email-rppt@linux.ibm.com


Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>