When PFC is enabled we should not proceed with setting the link flow control
parameters.  Also, always report the link flow Tx/Rx settings as off when
PFC is enabled.

Change-ID: Ib09ec58afdf0b2e587ac9d8851a5c80ad58206c4
Signed-off-by: NNeerav Parikh <neerav.parikh@intel.com>
Tested-By: NJack Morgan <jack.morgan@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>