clangdev should have a run_export on clang-{{ major_version }}

[SylvainCorlay]

Comment:

If a package has clangdev as a host dependency (links with clang-{{ major_version }}, and uses the cmake files that are available in clangdev, then they clearly will also depend on clang-{{ major_version }} at runtime.

It should probably be added as a run_export in the recipe for the clangdev output.

[h-vetinari]

Well, clang-{{ major_version}} brings a whole lot more than just the libs needed for linkage; shouldn't it be enough to propagate the run-exports for libclang & libclang-cpp?