Fix DUB dependencies (with cache description)

[rtbo]

Two PR has been merged into DUB which will help to use DUB packages with Meson:

• dlang/dub#2644
  • add the dub describe output the path of the built library in Dub's cache
• dlang/dub#2647
  • add dub build --deep switch to build a complete tree of static libraries

dub build --deep will build exactly the same libraries (same build-id) as the packages returned by dub describe. So for a complex dependency tree (e.g. vibe-d), a single command (entered by the user) will build all the needed sub-libraries, and then meson will be able to find them all in a single shot.

This PR fixes #11773 and supersedes #11798