- update to ghc-rpm-macros-0.5.1 and cabal2spec-0.21.1:
- drop doc and prof bcond
- use common_summary and common_description
- use ghc_name, ghc_binlib_package and ghc_pkg_deps
- build shared library
- drop X11_minver for now: it breaks macros
- drop redundant buildroot and its install cleaning