add %ghc_with_lib_for_ghci to enable building ghci library file

Normally not needed since ghci can now load .a files

ghc-rpm-macros.ghc

@@ -250,7 +250,7 @@ find %{buildroot} -type f -exec sh -c "file {} | grep -q 'dynamically linked'" \
 # ghc_lib_build_without_haddock [name] [version]
 %ghc_lib_build_without_haddock()\
 %global debug_package %{nil}\
-%cabal_configure %{!?without_prof:-p} %{!?ghc_without_shared:--enable-shared} %{?1:--docdir=%{_docdir}/ghc-%1-%2 --htmldir=%{ghclibdocdir}/%1-%2} \
+%cabal_configure %{!?without_prof:-p} %{!?ghc_without_shared:--enable-shared} %{?1:--docdir=%{_docdir}/ghc-%1-%2 --htmldir=%{ghclibdocdir}/%1-%2} %{?ghc_with_lib_for_ghci:--enable-library-for-ghci}\
 %cabal build\
 %{nil}