- Remove ocaml_native_compiler flag, assume native target
This flag puts too much burden on pkgs that use ocaml, but build
with their buildsystem instead of using dune

- Use bcond suse_ocaml_use_rpm_license_macro for license in filelist
- Add suse prefix to ocaml_native_compiler to avoid conflict
- Create Provides/Requires only for rpm variants which understand fileattrs
- Fix syntax for chmod of .cmxs
- Add conditional to disable debug_package macro when building with broken rpm variants