treewide: more accurate pandoc/shellcheck availability checks

The actual problem here is that there is no GHC bootstrap tarball for
RISC-V or LoongArch, so the right thing to check here is whether the
platform being used to build GHC has a bootstrap tarball available for
it.  This way, we'll do the right thing in all cases where such a
tarball isn't available, not just riscv64 and loongarch64, without
having to resort to tryEval, which could be hiding all sorts of
problems.

Since we need to refer to (unspliced) buildPackages.pandoc and
buildPackages.shellcheck in the conditionals, I've opted to remove the
pandoc and shellcheck inputs that would be spliced in
nativeBuildInputs and use buildPackages explicitly there as well, to
avoid confusingly having two different instances of the same package
around.

0 files changed, 0 insertions, 0 deletions