Revert "[ARM] pxa: remove now unnecessary dma_needs_bounce()"

[Russell King - ARM Linux]

On Mon, Mar 21, 2011 at 07:00:57PM -0700, Barry Song wrote:
> For sa1111, why don't PCB design just connect one sdram to bank0 and
> make software use bank0 as DMA bank if bank0 is not slower than
> bank1/2/3? If bank0 is same with bank1/2/3 in hardware timing, there
> is no reason to make a strange design which uses bank1/2/3 as DMA
> area.

Who knows why board and SoC designers do silly things.  If we could stop
that, the kernel would be *much* simpler.