Rename quiesce to drain to avoid confusion with the pseudo instruction.

Rename quiesce to drain to avoid confusion with the pseudo instruction.

src/cpu/simple/timing.cc:
src/cpu/simple/timing.hh:
src/python/m5/__init__.py:
src/python/m5/config.py:
src/sim/main.cc:
src/sim/sim_events.cc:
src/sim/sim_events.hh:
src/sim/sim_object.cc:
src/sim/sim_object.hh:
    Rename quiesce to drain.

--HG--
extra : convert_revision : fc3244a3934812e1edb8050f1f51f30382baf774