Unclear message when the Haskell Suite program could not be found

**Describe the bug**

If cabal can't find the specified Haskell Suite program, cabal gives the following error message.

cabal: The program 'haskell-suite' is required but it could not be found.

This is likely to mislead users into thinking they're missing a `haskell-suite` executable.

**To Reproduce**

```
$ cabal v1-install --haskell-suite -w program-name array
```

Where `program-name` is not a valid file (and it is not on the PATH).

**Expected behavior**
The error message clearly indicates that the program specified with `-w` could not be found.

cabal: The program 'program-name' is required but it could not be found.

**System information**
- Alpine Linux 3.10.2
- Cabal 2.4.1.0