Currently, when a trunk link goes down due to some fault, the driver
snapshots the fault code.  If the link then comes back up, meaning there is
no fault, the driver is not clearing the fault code so the sysfs link_state
entry reports old/stale data.

Revise the logic so that on successful link up the fault code is cleared.
Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>