x86, mm: s/PAGES_PER_ELEMENT/PAGES_PER_SECTION/

DISCONTIGMEM on x86-32 implements pfn -> nid mapping similarly to
SPARSEMEM; however, it calls each mapping unit ELEMENT instead of
SECTION.  This patch renames it to SECTION so that PAGES_PER_SECTION
is valid for both DISCONTIGMEM and SPARSEMEM.  This will be used by
the next patch to implement mapping granularity check.

This patch is trivial constant rename.

Signed-off-by: Tejun Heo <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Cc: Hans Rosenfeld <[email protected]>
Signed-off-by: H. Peter Anvin <[email protected]>
2 files changed