mm: replace various uses of num_physpages by totalram_pages

mm: replace various uses of num_physpages by totalram_pages

Sizing of memory allocations shouldn't depend on the number of physical
pages found in a system, as that generally includes (perhaps a huge amount
of) non-RAM pages.  The amount of what actually is usable as storage
should instead be used as a basis here.

Some of the calculations (i.e.  those not intending to use high memory)
should likely even use (totalram_pages - totalhigh_pages).

Signed-off-by: Jan Beulich <[email protected]>
Acked-by: Rusty Russell <[email protected]>
Acked-by: Ingo Molnar <[email protected]>
Cc: Dave Airlie <[email protected]>
Cc: Kyle McMartin <[email protected]>
Cc: Jeremy Fitzhardinge <[email protected]>
Cc: Pekka Enberg <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: "David S. Miller" <[email protected]>
Cc: Patrick McHardy <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>