patch applied (cabal): Use the same ReadP for all compilers, remove CPP hacks

[Ross Paterson]

On Mon, Mar 10, 2008 at 05:23:06PM -0700, Duncan Coutts wrote:
> Mon Mar 10 12:14:22 PDT 2008  Duncan Coutts <duncan at haskell.org>
>   * Use the same ReadP for all compilers, remove CPP hacks
>   If we're bundling a whole copy of ReadP then why bother trying to use
>   the version from the base package, especially when that requires hacks
>   to use the H98 version with some compilers and the non-H98 version in
>   base.

The benefit of using the base version is that ReadP parsers provided by
the Cabal library can be combined with parsers using the base version.