[ARM] Convert DMA cache handling to take const void * args

The DMA cache handling functions take virtual addresses, but in the
form of unsigned long arguments.  This leads to a little confusion
about what exactly they take.  So, convert them to take const void *
instead.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/common/dmabounce.c

@@ -321,12 +321,12 @@ unmap_single(struct device *dev, dma_addr_t dma_addr, size_t size,
 		DO_STATS ( device_info->bounce_count++ );
 
 		if (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL) {
-			unsigned long ptr;
+			void *ptr = buf->ptr;
 
 			dev_dbg(dev,
 				"%s: copy back safe %p to unsafe %p size %d\n",
-				__func__, buf->safe, buf->ptr, size);
-			memcpy(buf->ptr, buf->safe, size);
+				__func__, buf->safe, ptr, size);
+			memcpy(ptr, buf->safe, size);
 
 			/*
 			 * DMA buffers must have the same cache properties
@@ -336,7 +336,6 @@ unmap_single(struct device *dev, dma_addr_t dma_addr, size_t size,
 			 * bidirectional case because we know the cache
 			 * lines will be coherent with the data written.
 			 */
-			ptr = (unsigned long)buf->ptr;
 			dmac_clean_range(ptr, ptr + size);
 			outer_clean_range(__pa(ptr), __pa(ptr) + size);
 		}