Per-project linker choice is not honoured

## Context:

I'm converting a project to cabal, and it has many shell scripts with such invocations:

```bash
export USE_LINKER=lld

ghc -Wall -i../.. \
-odir ../../build \
-hidir ../../build \
../../libiced_hs.a \
${USE_LINKER+-optl -fuse-ld="$USE_LINKER"} \
main.hs
```

(https://github.com/ibaryshnikov/iced-hs/blob/5c7ad27deba8fad4f29df7d16d67881c21ca1508/examples/radio/build.sh#L7-L12)

However it's unclear to me how to create a working setup where `lld` is used reliably.

## Reproducer

```bash
$ git clone https://github.com/haskell-text/text-display
$ cd text-display
$ git switch use-lld
$ cabal build
```

```

: error:
Warning: Couldn't figure out linker information!
Make sure you're using GNU ld, GNU gold or the built in OS X linker, etc.
collect2: fatal error: cannot find ‘ld’
compilation terminated.
`gcc' failed in phase `Linker'. (Exit code: 1)
```

What is the preferred workflow these days?

Start by reproducing the failure with the text-display repository, its use-lld branch, and cabal build. Trace how the project-level linker choice reaches the GHC linking command; done means the configured lld choice is honored reliably without requiring a system ld.

Written by the indexing model from the issue text.