Blackfin arch: Add definition of dma_mapping_error

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>

diff --git a/include/asm-blackfin/dma-mapping.h b/include/asm-blackfin/dma-mapping.h
index 7a77d7f..282fabc 100644
--- a/include/asm-blackfin/dma-mapping.h
+++ b/include/asm-blackfin/dma-mapping.h
@@ -15,6 +15,8 @@
 #define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
 #define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
 
+#define dma_mapping_error
+
 /*
  * Map a single buffer of the indicated size for DMA in streaming mode.
  * The 32-bit bus address to use is returned.