[RFC] librseq updates following glibc rseq integration

[Mathieu Desnoyers]

Hi Florian,

I have pushed some updates into librseq following integration of rseq
into glibc:

https://git.kernel.org/pub/scm/libs/librseq/librseq.git/

This mostly adapts to the way glibc manages __rseq_abi registration.
The interesting bits are here:

https://git.kernel.org/pub/scm/libs/librseq/librseq.git/tree/src/rseq.c

There is no official release of librseq yet, so we have time to adapt and
do whatever we need.

I have re-integrated a test-case from the Linux kernel selftests into
librseq as well.

Feedback is welcome!

Thanks,

Mathieu

-- 
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com