Remove dma_cache_(wback|inv|wback_inv) functions

dma_cache_(wback|inv|wback_inv) were the earliest attempt on a generalized
cache managment API for I/O purposes.  Originally it was basically the raw
MIPS low level cache API exported to the entire world.  The API has
suffered from a lack of documentation, was not very widely used unlike it's
more modern brothers and can easily be replaced by dma_cache_sync.  So
remove it rsp.  turn the surviving bits back into an arch private API, as
discussed on linux-arch.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Paul Mackerras <paulus@samba.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Kyle McMartin <kyle@parisc-linux.org>
Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/sh/mm/consistent.c

@@ -34,7 +34,7 @@ void *consistent_alloc(gfp_t gfp, size_t size, dma_addr_t *handle)
 	/*
 	 * We must flush the cache before we pass it on to the device
 	 */
-	dma_cache_wback_inv(ret, size);
+	__flush_purge_region(ret, size);
 
 	page = virt_to_page(ret);
 	free = page + (size >> PAGE_SHIFT);
@@ -68,13 +68,13 @@ void consistent_sync(void *vaddr, size_t size, int direction)
 
 	switch (direction) {
 	case DMA_FROM_DEVICE:		/* invalidate only */
-		dma_cache_inv(p1addr, size);
+		__flush_invalidate_region(p1addr, size);
 		break;
 	case DMA_TO_DEVICE:		/* writeback only */
-		dma_cache_wback(p1addr, size);
+		__flush_wback_region(p1addr, size);
 		break;
 	case DMA_BIDIRECTIONAL:		/* writeback and invalidate */
-		dma_cache_wback_inv(p1addr, size);
+		__flush_purge_region(p1addr, size);
 		break;
 	default:
 		BUG();