Haskell for openSUSE

To generate the Haskell OBS repositories for openSUSE Linux, perform the following steps:

Clone this repository with the --recursive flag or, alternatively, run
```
 $ git submodule update --init
```
in your checked-out copy.

Check out the devel:languages:haskell:ghc-8.10.x and devel:languages:haskell:ghc-9.2.x and OBS repositories in a _build/ sub-directory by running:

 $ mkdir -p _build
 $ osc co devel:languages:haskell:ghc-8.10.x -o _build/ghc-8.10.x
 $ osc co devel:languages:haskell:ghc-9.2.x -o _build/ghc-9.2.x

Run cabal update.
Execute cabal run -- cabal2obs to re-generate all spec files. Note that the initial run of the build system might take a while. Once the initial build has succeeded, further re-runs will be very fast.
Inspect the build/ghc-* hierarchies with osc status and osc diff to make sure that all generated changes look reasonable. There should be no modifications in any of these projects:
- ghc
- ghc-bootstrap
- ghc-rpm-macros

Commit:

 $ pushd _build/ghc-8.10.x && ../../tools/commit && popd
 $ pushd _build/ghc-9.2.x && ../../tools/commit && popd