IB/ipath: ipath_skip_sge() can break if num_sge > 1

ipath_skip_sge() doesn't exactly duplicate the side effects of
ipath_copy_sge() if num_sge > 1 since it doesn't decrement ss->num_sge.
This could result in the sg_list being accessed out of bounds.
Since ipath_skip_sge() is almost always called with num_sge == 1,
the original "optimization" is almost never used.

Signed-off-by: Ralph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

drivers/infiniband/hw/ipath/ipath_verbs.c

@@ -191,10 +191,6 @@ void ipath_skip_sge(struct ipath_sge_state *ss, u32 length)
 {
 	struct ipath_sge *sge = &ss->sge;
 
-	while (length > sge->sge_length) {
-		length -= sge->sge_length;
-		ss->sge = *ss->sg_list++;
-	}
 	while (length) {
 		u32 len = sge->length;