[PATCH v3 5/8] dma-direct: Turn zone_dma_bits default value into a define

[Christoph Hellwig]

On Wed, Oct 14, 2020 at 09:12:07PM +0200, Nicolas Saenz Julienne wrote:
> Set zone_dma_bits default value through a define so as for architectures
> to be able to override it with their default value.

Architectures can do that already by assigning a value to zone_dma_bits
at runtime.  I really do not want to add the extra clutter.