[PATCH, newlib] Allow locking routine to be retargeted

[Thomas Preudhomme]

On 13/12/16 20:12, Freddie Chopin wrote:
> Great!
>
> I've already managed to compile the toolchain for ARM, now I'm trying
> to implement all these "retargeting" functions and required lock
> objects. We'll see how it works (;
>
> BTW - maybe it would be better to leave the functions undefined and
> provide the stubs only in libnosys.a? This would be consistent with
> other newlib stubs (like _sbrk_r(), _read_r() and so on)?

I need to look into how does that work when not using libnosys.a. I'll also add 
the extern C as per your suggestion.

Thanks,

Thomas