ixgbe: Fix 82599 multispeed fiber link issues due to Tx laser flapping

Fix 82599 link issues during driver load and unload test using multi-speed
10G & 1G fiber modules. When connected back to back sometime 82599 multispeed
fiber modules would link at 1G speed instead of 10G highest speed, due to a
race condition in autotry process involving Tx laser flapping. Move autotry
autoneg-37 tx laser flapping process from multispeed module init setup
to driver unload. This will alert the link partner to restart its
autotry process when it tries to establish the link with the link partner

Signed-off-by: Mallikarjuna R Chilakala <mallikarjuna.chilakala@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>