Stop using omisc.h and move relevant functions to better places

Stop using omisc.h and move relevant functions to better places
while converting them to C++

base/intmath.hh:
    Add some functions that were previously defined elsewhere in C
base/misc.cc:
    Use the C++ version of memUsage, and sort #includes
sim/prog.cc:
    Stop using the old macro versions of various functions and use
    the new ones defined in intmath.hh
sim/sim_events.cc:
    Stop using the old C versions of various functions and use
    the new ones defined in hostinfo.hh

--HG--
extra : convert_revision : 15d1f24d2aff4254c745eea6070cb230dd37b8d2