- Make sure forward headers have the iwyu pragma to always keep them
- Make sure we always include the daemon specific forward header
instead of shared-forward.h
- Remove shared-forward.h include where the daemon specific forward
header is already included
Let's not leak details from src/shared and src/libsystemd into
src/basic, even though you can't actually do anything useful with
just forward declarations from src/shared.
The sd-forward.h header is put in src/libsystemd/sd-common as we
don't have a directory for shared internal headers for libsystemd
yet.
Let's also rename forward.h to basic-forward.h to keep things
self-explanatory.
Daan De Meyer