mm: move page zone helpers from mm.h to mmzone.h

It makes more sense to have these helpers in zone specific header
file, rather than the generic mm.h

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Alex Sierra <[email protected]>
Cc: Alistair Popple <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: Felix Kuehling <[email protected]>
Cc: Jason Gunthorpe <[email protected]>
Cc: Jerome Glisse <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Ralph Campbell <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
3 files changed