synopsis: Treat `pkg:sublib` dependency syntax as is in `cabal-version: 3.4`
issues: #6083
prs: #6907 #6893
significance: significant

description: {

In `cabal-version: 3.4` cabal files the dependency definition

```cabal
build-depends: somesublib
```

is not using in-package sublibraries. You have to be explicit and write

```cabal
build-depends: thispkg:somesublib
```

This fixes an issue, where it was impossible to refer to extenral
library, if you had sublibrary of the same name.

}