sh: Fix libata build.

Drop virt_to_bus() from sg_dma_address() so libata builds.
While we're at it, move sg_dma_address() and sg_dma_len()
from pci.h to scatterlist.h.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/include/asm-sh/scatterlist.h b/include/asm-sh/scatterlist.h
index 7b91df1..d19e7cd 100644
--- a/include/asm-sh/scatterlist.h
+++ b/include/asm-sh/scatterlist.h
@@ -10,4 +10,13 @@
 
 #define ISA_DMA_THRESHOLD (0x1fffffff)
 
+/* These macros should be used after a pci_map_sg call has been done
+ * to get bus addresses of each of the SG entries and their lengths.
+ * You should only work with the number of sg entries pci_map_sg
+ * returns, or alternatively stop on the first sg_dma_len(sg) which
+ * is 0.
+ */
+#define sg_dma_address(sg)	((sg)->dma_address)
+#define sg_dma_len(sg)		((sg)->length)
+
 #endif /* !(__ASM_SH_SCATTERLIST_H) */