Get SPARC to the point that it starts running. Add ability to load the ROM bin files...

Get SPARC to the point that it starts running. Add ability to load the ROM bin files, cleanup lockstep printing a bit
Since we don't have a platform yet, you need to comment out the default responder stuff in Bus.py to make it work.

SConstruct:
    Add TARGET_ISA to the list of environment variables that end up in the build_env for python
configs/common/FSConfig.py:
    add a simple SPARC system to being testing with, you'll need to change makeLinuxAlphaSystem to makeSparcSystem in fs.py for now
src/SConscript:
    add a raw file object, at least until we get more info about how to compile openboot properly
src/arch/sparc/system.cc:
src/arch/sparc/system.hh:
    add parameters for ROM files (OBP/Reset/Hypervisor), a ROM, load files into ROM
src/base/loader/object_file.cc:
src/base/loader/object_file.hh:
    add option to try raw when nothing works
src/cpu/exetrace.cc:
    cleanup lockstep printing a little bit
src/cpu/m5legion_interface.h:
    change the instruction to be 32 bits because it is
src/mem/physical.cc:
    fix assert that doesn't work if memory starts somewhere above 0
src/python/m5/objects/BaseCPU.py:
    Add if statement to choose between sparc tlbs and alpha tlbs
src/python/m5/objects/System.py:
    Add a sparc system that sets the rom addresses correctly
src/python/m5/params.py:
    add the ability to add Addr() together

--HG--
extra : convert_revision : bbbd8a56134f2dda2728091f740e2f7119b0c4af