ARM: pxa: transition to dmaengine phase 1

In order to slowly transition pxa to dmaengine, the legacy code will now
rely on dmaengine to request a channel.

This implies that PXA architecture selects DMADEVICES and PXA_DMA,
which is not pretty. Yet it enables PXA drivers to be ported one by one,
with part of them using dmaengine, and the other part using the legacy
code.

Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
diff --git a/arch/arm/mach-pxa/pxa3xx.c b/arch/arm/mach-pxa/pxa3xx.c
index bd4cbef..aa85ec1 100644
--- a/arch/arm/mach-pxa/pxa3xx.c
+++ b/arch/arm/mach-pxa/pxa3xx.c
@@ -431,6 +431,7 @@
 		if (of_have_populated_dt())
 			return 0;
 
+		pxa2xx_set_dmac_info(32);
 		ret = platform_add_devices(devices, ARRAY_SIZE(devices));
 		if (ret)
 			return ret;