powerpc: of_parse_dma_window should take a __be32 *dma_window

We pass dma_window to of_parse_dma_window as a void * and then
run through hoops to cast it back to a u32 array. In the process
we lose endian annotation.

Simplify it by just passing a __be32 * down.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/platforms/cell/iommu.c

@@ -697,7 +697,7 @@ static int __init cell_iommu_get_window(struct device_node *np,
 					 unsigned long *base,
 					 unsigned long *size)
 {
-	const void *dma_window;
+	const __be32 *dma_window;
 	unsigned long index;
 
 	/* Use ibm,dma-window if available, else, hard code ! */