RDS: properly use sg_init_table

This is only needed to keep debugging code from bugging.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/net/rds/ib_recv.c b/net/rds/ib_recv.c
index f25c483..a2f5f6f 100644
--- a/net/rds/ib_recv.c
+++ b/net/rds/ib_recv.c
@@ -282,6 +282,7 @@
 		if (!frag)
 			return NULL;
 
+		sg_init_table(&frag->f_sg, 1);
 		ret = rds_page_remainder_alloc(&frag->f_sg,
 					       RDS_FRAG_SIZE, page_mask);
 		if (ret) {