Drop debian/r-recommended.links

Fix FTBFS in v2024+:

In Debian /usr/share/doc/r-recommended doesn't exist, so a link is created to /usr/share/doc/r-base-core.

But in Apertis, /usr/share/doc/r-recommended contains files generated by dh_setup_copyright which makes it impossible to create a link.

Signed-off-by: Dylan Aïssi dylan.aissi@collabora.com