Virtualize sinic

Virtualize sinic
separate the rx thread and tx thread and get rid of the dedicated flag.

dev/ns_gige.cc:
dev/ns_gige.hh:
dev/ns_gige_reg.h:
python/m5/objects/Ethernet.py:
    dedicated flag goes away, we have new individual flags for
    rx thread and tx thread
dev/sinic.cc:
    Virtualize sinic
    - The io registers are replicated many times in memory, allowing the NIC to
    differentiate among several virtual interfaces.
    - On the TX side, this allows multiple CPUs to initiate transmits at the same
    time without locking in the software.  If a partial packet is transmitted,
    then the state machine blocks waiting for that virtual interface to complete
    its packet.  Then the state machine will move on to the next virtual
    interface.  The commands are kept in fifo order.
    - On the RX side, multiple partial transmits can be simultaneously done.
    Though a packet does not deallocate its fifo space until all preceeding
    packets in the fifo are deallocated.  To enable multiple receives, it
    is necessary for each virtual nic to keep its own information about its
    progress through the state machine.
dev/sinic.hh:
    Virtualize sinic
    Receive state must be virtualized since we allow the receipt of packets in
    parallel.
dev/sinicreg.hh:
    Virtualize sinic
    separate rx thread and tx thread
    create a soft interrupt and add a command to trigger it.
    pad out the reserved bits in the RxDone and TxDone regs

--HG--
extra : convert_revision : c10bb23a46a89ffd1e08866c1f1621cb98069205