* sim-main.h (ExceptionCause): Add new values for MIPS32
and MIPS64: MDMX, MCheck, CacheErr. Update comments
for DebugBreakPoint and NMIReset to note their status in
MIPS32 and MIPS64.
(SignalExceptionMDMX, SignalExceptionWatch, SignalExceptionMCheck)
(SignalExceptionCacheErr): New exception macros.