e1000 missing statistics

The E1000 emulation is missing several counters that are used by other software.

The following would be useful:
  Good bytes receive counter GORCH/GORCL
  Good bytes transmit counter GOTCH/GOTCL
Broadcast packets sent/received
Multicast packets sent/received.

Looks like these counters have been implemented here:
http://git.qemu-project.org/?p=qemu.git;a=commitdiff;h=3b27430177498a1728b6