ixgbe: fix LED blink logic to check for link

ixgbe: fix LED blink logic to check for link

Previously the driver would force link without checking whether the link was
already established. This caused some inconsistencies in the LED blink rate.

Do not force link if link is already up.

(cherry picked from commit 8d233633bab501567841aaa2935963fb908c9523)
Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Joe Jin <joe.jin@oracle.com>