[PATCH 5/7] elf: Enable relro for static build

[Florian Weimer]

* Adhemerval Zanella:

> About testing, I am not sure what kind of coverage we are aiming
> here. My initial approach would to check if a write on a variable
> set to .data.rel.so does trigger a SEGSEGV signal and check with
> some different combinations (-z now, -z lazy, static, dynamic,
> pie, nopie). Do you have something more elaborated in mind?

Yes, that's what my tests do.  I will post them once we've stabilized
the dynamic linker again.