There is a known issue in the 82577 and 82578 device that can cause a hang
in the device hardware during traffic stress; the current workaround in the
driver is to disable transmit flow control by default.  If the user enables
transmit flow control and the device hang occurs, provide a message in the
syslog suggesting to re-enable the workaround.
Signed-off-by: NBruce Allan <bruce.w.allan@intel.com>
Tested-by: NJeff Pieper <jeffrey.e.pieper@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>