parisc: move internal implementation details out of <asm/dma-mapping.h>

Move everything that is not required for the public facing DMA API out
of <asm/dma-mapping.h> and into a new drivers/parisc/iommu.h header.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Helge Deller <deller@gmx.de>

drivers/parisc/hppb.c

@@ -23,6 +23,8 @@
 #include <asm/hardware.h>
 #include <asm/parisc-device.h>
 
+#include "iommu.h"
+
 struct hppb_card {
 	unsigned long hpa;
 	struct resource mmio_region;