Most ARM machines don't need a special "DMA" memory zone, and
when configured out, the kernel becomes a bit smaller:
| text data bss dec hex filename
|3826182 102384 111700 4040266 3da64a vmlinux
|3823593 101616 111700 4036909 3d992d vmlinux.nodmazone
This is because the system now has only one zone total which effect is
to optimize away many conditionals in page allocation paths.
So let's configure this zone only on machines that need split zones.
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
3bca103a1e