Blackfin arch: add dma mapping stub for musb driver port

Signed-off-by: Bryan Wu <cooloney@kernel.org>

diff --git a/arch/blackfin/include/asm/dma-mapping.h b/arch/blackfin/include/asm/dma-mapping.h
index 1a13c2f..ede748d 100644
--- a/arch/blackfin/include/asm/dma-mapping.h
+++ b/arch/blackfin/include/asm/dma-mapping.h
@@ -80,4 +80,15 @@
 extern void dma_unmap_sg(struct device *dev, struct scatterlist *sg,
 		      int nhwentries, enum dma_data_direction direction);
 
+static inline void dma_sync_single_for_cpu(struct device *dev,
+					dma_addr_t handle, size_t size,
+					enum dma_data_direction dir)
+{
+}
+
+static inline void dma_sync_single_for_device(struct device *dev,
+					dma_addr_t handle, size_t size,
+					enum dma_data_direction dir)
+{
+}
 #endif				/* _BLACKFIN_DMA_MAPPING_H */