Major update to sinic to support VSINIC better

Major update to sinic to support VSINIC better

dev/sinic.cc:
    - Size the virtualRegs array based on the configured value
    - Add debugging stuff for uniquely identifying vnic usage
    - Only count totally unprocessed packets when notifying via RxDone
    - Add initial virtual address support
    - Fix some bugs in accessing packets out of order to make sure that
    busy packets are processed first
    - Add fifo watermark stuff
    - Make number of vnics, zero/delay copy and watermarks parameters
dev/sinic.hh:
    add rxUnique and txUnique to uniquely identify tx and rx VNICs
    Create a separate list of Busy VNICs since more than one might
    be busy and we want to service those first
    Add more watermark stuff and new parameters
dev/sinicreg.hh:
    Make the number of virtual nics a read-only parameter
    add bits for ZeroCopy/DelayCopy
    rename Virtual to Vaddr so it's not ambiguous
    Add a flag for TxData/RxData to indicate a virtual address
    Report rxfifo status in RxDone
python/m5/objects/Ethernet.py:
    add more options for the fifo thresholds
    add number of vnics as a parameter
    add copy type as a parameter
    add virtual addressing as a parameter

--HG--
extra : convert_revision : 850e2433b585d65469d4c5d85ad7ca820db10f4a