During (re)init setting the IFF_DRV_RUNNING flag after
enabling interrupts could lead to missing those asserted
immediately and blocking the queues. Set the flag first
to prevent that.
Driver did not check if LRO control structures were already
initialized and not freed them before allocating new ones.
It could lead to kernel panic under heavy RX traffic.
Also free the structures before deallocating RX rings
to avoid memory leak.
This patch is for stable/11 branch only as the ixl driver
in 12 and CURRENT uses iflib, where it is already fixed.