[SCSI] libfcoe: Do not pad FIP keep-alive to full frame size

According to the FC-BB-5 Rev2.0, 7.8.6.2, we should not pad FIP keep-alive
frames.

Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
diff --git a/drivers/scsi/fcoe/libfcoe.c b/drivers/scsi/fcoe/libfcoe.c
index 2988b71..3c501d4 100644
--- a/drivers/scsi/fcoe/libfcoe.c
+++ b/drivers/scsi/fcoe/libfcoe.c
@@ -351,8 +351,7 @@
 	if (!fcf || !fc_host_port_id(lp->host))
 		return;
 
-	len = fcoe_ctlr_fcoe_size(fip) + sizeof(struct ethhdr);
-	BUG_ON(len < sizeof(*kal) + sizeof(*vn));
+	len = sizeof(*kal) + ports * sizeof(*vn);
 	skb = dev_alloc_skb(len);
 	if (!skb)
 		return;