Intrdocue igb device emulation

Intrdocue igb device emulation

This change introduces emulation for the Intel 82576 adapter, AKA igb.
The details of the device will be provided by the documentation that
will follow this change.

This initial implementation of igb does not cover the full feature set,
but it selectively implements changes necessary to pass tests of Linut
Test Project, and Windows HLK. The below is the list of the implemented
changes; anything not listed here is not implemented:

New features:
- igb advanced descriptor handling
- Support of 16 queues
- SRRCTL.BSIZEPACKET register field
- SRRCTL.RDMTS register field
- Tx descriptor completion writeback
- Extended RA registers
- VMDq feature
    - MRQC "Multiple Receive Queues Enable" register field
    - DTXSWC.Loopback_en register field
    - VMOLR.ROMPE register field
    - VMOLR.AUPE register field
    - VLVF.VLAN_id register field
    - VLVF.VI_En register field
- VF
    - Mailbox
    - Reset
- Extended interrupt registers
- Default values for IGP01E1000 PHY registers

Removed features:
- e1000e extended descriptor
- e1000e packet split descriptor
- Legacy descriptor
- PHY register paging
- MAC Registers
    - Legacy interrupt timer registers
    - Legacy EEPROM registers
    - PBA/POEM registers
    - RSRPD register
    - RFCTL.ACKDIS
    - RCTL.DTYPE
- Copper PHY registers

Misc:
- VET register format
- ICR register format

Signed-off-by: Gal Hammer <gal.hammer@sap.com>
Signed-off-by: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
[Jason: don't abort on msi(x)_init()]
Signed-off-by: Jason Wang <jasowang@redhat.com>