sonic-visualiser: use propagated build inputs

With nixpkgs switching to gcc 14 in stdenv recently, the newly enabled-
by-default `-Wincompatible-pointer-types` causes a build failure for
`sonic-visualiser`. This is due to a dependency on an outdated
`librdf_raptor` instead of the current `librdf_raptor`.

This patch removes the explicit dependency on `librdf_raptor` and
`librdf_rasqal` in favor of propagated build inputs from `redland`.