Add script 30-prelink-update.sh to genup

[iperi]

I created script for updating prelinked binaries. Command taken from: https://wiki.gentoo.org/wiki/Prelink#Prelink_Usage.

This script is not tested, but should work. I am not using prelink so I can't test it.

[sakaki-]

31 Oct 2020: sadly, due to legal obligations arising from a recent change in my 'real world' job, I must announce I am standing down as maintainer of this project with immediate effect. For the meantime, I will leave the repo up (for historical interest, and since the ebuilds etc. may be of use to others); however, I plan no further updates, nor will I be accepting / actioning further pull requests or bug reports from this point. Email requests for support will also have to be politely declined, so, please treat this as an effective EOL notice.

For further details, please see my post here.

If you have used my EFI Guide (and this repo) to install your PC-based Gentoo system, it should still continue to work for some time, but you should now take steps to migrate to a baseline Gentoo Handbook install (since the underlying tools, such as buildkernel, will also now no longer be supported and may eventually fail as more modern kernels etc. are released).

With sincere apologies, sakaki ><