Merge remote-tracking branch 'stefanha/net' into staging

* stefanha/net:
  rtl8139: preserve link state across device reset
  e1000: no need auto-negotiation if link was down
  net: clean up network at qemu process termination
  e1000: Discard oversized packets based on SBP|LPE

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>