powerpc/mm: enable HAVE_MOVE_PMD support

mremap HAVE_MOVE_PMD/PUD optimization time comparison for 1GB region:
1GB mremap - Source PTE-aligned, Destination PTE-aligned
  mremap time:      2292772ns
1GB mremap - Source PMD-aligned, Destination PMD-aligned
  mremap time:      1158928ns
1GB mremap - Source PUD-aligned, Destination PUD-aligned
  mremap time:        63886ns

Link: https://lkml.kernel.org/r/20210616045735.374532-4-aneesh.kumar@linux.ibm.comSigned-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Hugh Dickins <hughd@google.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Kalesh Singh <kaleshsingh@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/powerpc/platforms/Kconfig.cputype

@@ -102,6 +102,8 @@ config PPC_BOOK3S_64
 	select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE
 	select ARCH_SUPPORTS_HUGETLBFS
 	select ARCH_SUPPORTS_NUMA_BALANCING
+	select HAVE_MOVE_PMD
+	select HAVE_MOVE_PUD
 	select IRQ_WORK
 	select PPC_MM_SLICES
 	select PPC_HAVE_KUEP