[llvm] [llvm-readobj, ELF] Support for reading binary has more than PN_XNUM segments (PR #162648)

[via llvm-commits]

aokblast wrote:

> > > > > I'd also recommend you have an llvm-readobj PR and an llvm-objcopy PR, since the two are independent (or at least, llvm-readobj shouldn't depend on llvm-objcopy as a minimum).
> > > > > The test would fail since objcopy test use readobj to parse the result. Does it matter?
> > > 
> > > 
> > > Make the llvm-objcopy test depend on the llvm-readobj one. Use one of the stacked pull request tools to set this up. Alternatively, simply don'r put the llvm-objcopy review up until the llvm-readobj one has landed.
> > 
> > 
> > Can I recreate a PR for using user branch in llvm instead of my private branch? Since I am unable to change the source branch to the User branch and you have not left any comment on my code.
> 
> I'm not sure I entirely follow what you're asking here, but as long as you follow one of the recommendations in https://llvm.org/docs/GitHub.html#stacked-pull-requests, it's fine to do what you want to do, including closing this PR and creating new ones.

I mean that method 1 and method 3 in stacked-pull-requests tutorial need the commit bit in llvm, which I didn't have when I submit these two patches. And method 2 is not suitable in here since the ELF.h patch have been modified too much times.
Now I have commit bit so that I can use method 1 or method 3 by creating a user branch and close this PR then recreate a PR with  user branch.

https://github.com/llvm/llvm-project/pull/162648