From: "Mike Rapoport (IBM)" <rppt@xxxxxxxxxx>
When deferred initialization of struct pages is enabled, page_ext_init()
must be called after all the deferred initialization is done, but there
is no point to keep it a separate call from kernel_init_freeable() right
after page_alloc_init_late().
Fold the call to page_ext_init() into page_alloc_init_late() and
localize deferred_struct_pages variable.
Signed-off-by: Mike Rapoport (IBM) <rppt@xxxxxxxxxx>