avr32: migrate cache functions

Unfortunately the avr32 cache implementation has another API than the one
described in common.h. Migrate the flush/invalidate dcache functions to the
common API to be usable in device drivers.

Signed-off-by: Andreas Bießmann <andreas.devel@googlemail.com>
CC: Josh Wu <josh.wu@atmel.com>
diff --git a/arch/avr32/lib/board.c b/arch/avr32/lib/board.c
index 7680102..bf0997f 100644
--- a/arch/avr32/lib/board.c
+++ b/arch/avr32/lib/board.c
@@ -65,8 +65,8 @@
 	printf("DMA: Using memory from 0x%08lx to 0x%08lx\n",
 	       dma_alloc_start, dma_alloc_end);
 
-	dcache_invalidate_range(cached(dma_alloc_start),
-				dma_alloc_end - dma_alloc_start);
+	invalidate_dcache_range((unsigned long)cached(dma_alloc_start),
+				dma_alloc_end);
 }
 
 void *dma_alloc_coherent(size_t len, unsigned long *handle)