radv: make device extension setup dynamic

Each physical device may have different extensions than one another.
Furthermore, depending on the software stack, some extensions may not be
accessible.

If an extension is conditional, it can be registered only when
necessary.

v2: removed unused function and fixed indentation

Signed-off-by: Andres Rodriguez <andresx7@gmail.com>
Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
2 files changed