Remove uses of ccall from PackedString
PackedString still uses ccall which is deprecated. It should use the new FFI libraries instead.
Edited by Simon Marlow
Due to a large amount of spam we do not allow new users to create repositories, they are "external" users. If you are a new user and want to create a repository, for example for forking GHC, open a new issue on ghc/ghc using the "get-verified" issue template
PackedString still uses ccall which is deprecated. It should use the new FFI libraries instead.