installation: documentation is built as the same user as the make install target is issued

When I do: ./configure && make && sudo make install documentation is built during last command in build/ directory. This leads to a situation, where user can't remove this directory before next build without sudo.

Expected:

• ./configure && make && make doc && sudo make install && rm -rf build succeeds (and installs documentation)
• ./configure && make && sudo make install && rm -rf build succeeds (but doesn't install documentation)

@spaghettisalat do you think it is something feasible? make install would require to check, if documentation is built. Alternatively we could make a separate target make install_doc, but I better like the proposed approach.