Add system event and cause code definitions needed for exception
handling in sysemu mode. Add privilege checks that raise exceptions
for guest/supervisor-only instructions executed without appropriate
privilege.
Expose hex_gen_exception_end_tb() via translate.h (previously the
static gen_exception_end_tb) so that it can be called from the
generated privileged-instruction TCG stubs.
Reviewed-by: Taylor Simpson <ltaylorsimpson@gmail.com>
Signed-off-by: Brian Cain <brian.cain@oss.qualcomm.com>