Support for Tsunami coming along... RTC, PIC working, UART in progress

Support for Tsunami coming along... RTC, PIC working, UART in progress

dev/tsunami_io.cc:
    PIC, PIT, RTC implementation for tsunami working so far
dev/tsunami_io.hh:
    PIT, PIC, RTC implementation for tlaser working so far
dev/tsunamireg.h:
    Added RTC defines
kern/linux/linux_system.cc:
    wrote cycle frequency into variable so linux doesn't probe for it.
    The support exists, but it takes two seconds of time to do on a real
    machine, so forever in the simulator.

--HG--
extra : convert_revision : e0ed7f271ece4ed69c06af35d1b0e8ed848cd138