Commit d309a46e, entitled
"tg3: 5719: Prevent tx data corruption", was supposed to contain the tx
margin adjustment but it looks like it somehow was omitted.  This patch
fixes the problem.
Signed-off-by: NMatt Carlson <mcarlson@broadcom.com>
Reviewed-by: NMichael Chan <mchan@broadcom.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>