blackfin: fix sg fallout

Signed-off-by: NAdrian Bunk <bunk@kernel.org>
Signed-off-by: NJens Axboe <axboe@carl.home.kernel.dk>

arch/blackfin/kernel/dma-mapping.c

@@ -35,6 +35,7 @@
 #include <linux/device.h>
 #include <linux/dma-mapping.h>
 #include <linux/io.h>
+#include <linux/scatterlist.h>
 #include <asm/cacheflush.h>
 #include <asm/bfin-global.h>