The scratch memory for kexec handover is used to bootstrap the
kexec'ed kernel. It is only needed when CONFIG_KEXEC_HANDOVER
is enabled and only if it is a KHO boot. Add checks to prevent
marking a KHO scratch region unless needed.

CONFIG_MEMBLOCK_KHO_SCRATCH is also removed as its only selected
by KEXEC_HANDOVER.

v1 -> v2:
- Remove CONFIG_MEMBLOCK_KHO_SCRATCH (Kiryl Shutsemau)
- Move memblock_mark/clear_kho_scratch under alread existing
  CONFIG_KEXEC_HANDOVER in memblock.c.

Usama Arif (2):
  mm/memblock: remove CONFIG_MEMBLOCK_KHO_SCRATCH option
  mm/memblock: only mark/clear KHO scratch memory when needed

 include/linux/memblock.h |  2 +-
 kernel/Kconfig.kexec     |  1 -
 mm/Kconfig               |  4 ---
 mm/memblock.c            | 78 +++++++++++++++++++++++-----------------
 4 files changed, 47 insertions(+), 38 deletions(-)

-- 
2.47.3