I've got a new build of the RT kernel for Fedora 22 based on 4.0.8. You can find it here:
Note that I should have a 4.1 release landing soonish. I've built for i686, x86_64, armv7hl,
and aarch64. If you would like another arch, let me know and I will see about building for
it. Just keep in mind that I likely would be unable to test the resulting kernel.
I have also built this same kernel for Fedora 23 for all three primary architectures.