gating.yaml only use tier0.functional, not scratch-build.validation.
The scratch-build.validation is for rebuilding the kernel, we don't
really need that as gating rule, since valgrind isn't part of the
kernel build chain.
plans/ci.fmf: Use tmt, not beakerlib, for how.
beakerlib is deprecated.
tests/quick-valgrind-sanity/main.fmf recommend only valgrind[-devel], gcc and make
This test doesn't use c++, fortran or 32bit glibc-devel.
