Set syscall return value from trace unconditionally during replay.
Remove emu_ret now that it's no longer used.
During replay, ignore num_emu_args and just reapply all recorded-data records for the current trace frame.
Automated reformat
Remove num_emu_args now that it's no longer used.
Remove no-longer-needed replay_syscall code
We no longer need num_emu_args in the syscall_defs table.
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