Duplicate events for 32-bit compatible syscall probes

[Aryeh Weinreb]

Hi,

While using some syscall.mq_* probes on 32bit on x86_64 I am getting
duplicate events.

Looking into ipc/compat_mq.c it seems that the compat_sys_mq calls are
just wrappers for the sys_mq ones.
Although, sometimes the compat calls can return EFAULT without calling
the non-compat versions.

It would be nice to only get one event for each system call without
missing any calls.

I am using an RHEL 6 build of systemtap version 1.8.

Thanks,
Aryeh