[bug#67896] [PATCH] gnu: ghc-9.2: Make Cabal respect GHC_PACKAGE_PATH

[Sören Tempel]

If we don't want to patch the vendored Cabal version shipped by GHC
itself, we could also explore packaging Cabal separately and making
cabal-install depend on that. However, given that Setup.hs also uses
Distribution.Simple and that there are several places in Guix itself
where we need to unset GHC_PACKAGE_PATH atm, I personally believe it
to be preferable to fix the vendored version.

Lars, what do you think?

Greetings
Sören