Fix problems with unCacheable addresses in timing-coherence

Fix problems with unCacheable addresses in timing-coherence

src/base/traceflags.py:
src/mem/physical.cc:
    Add debug falgs fro physical memory accesses
src/mem/cache/cache_impl.hh:
    Snoops to uncacheable blocks should not happen
src/mem/cache/miss/miss_queue.cc:
    Set the size properly on unCacheable accesses

--HG--
extra : convert_revision : fc78192863afb11fc7c591fba169021b9e127d16