lib/scatterlist: Remove leftover from sg_page_iter comment

Commit d901b276 ("lib/scatterlist: Provide a DMA page iterator") added
the sg DMA iterator but a leftover remained in the sg_page_iter
documentation as you cannot get the page dma address (only the page
itself), fix it.
Signed-off-by: Gal Pressman <galpress@amazon.com>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

include/linux/scatterlist.h

@@ -340,11 +340,11 @@ int sg_alloc_table_chained(struct sg_table *table, int nents,
  * sg page iterator
  *
  * Iterates over sg entries page-by-page.  On each successful iteration, you
- * can call sg_page_iter_page(@piter) to get the current page and its dma
- * address. @piter->sg will point to the sg holding this page and
- * @piter->sg_pgoffset to the page's page offset within the sg. The iteration
- * will stop either when a maximum number of sg entries was reached or a
- * terminating sg (sg_last(sg) == true) was reached.
+ * can call sg_page_iter_page(@piter) to get the current page.
+ * @piter->sg will point to the sg holding this page and @piter->sg_pgoffset to
+ * the page's page offset within the sg. The iteration will stop either when a
+ * maximum number of sg entries was reached or a terminating sg
+ * (sg_last(sg) == true) was reached.
  */
 struct sg_page_iter {
 	struct scatterlist	*sg;		/* sg holding the page */