- Improve Makefile logic: instead of breaking the port when
libboinc_graphics2.a is not found and the X11 option is selected, include
it as a build dependency (which had a hardcoded trigger before).
- Move astro/boinc-setiathome-enhanced (which this port borrows sources from)
to the build dependencies to please Tinderbox, however it fails.
Feature safe: yes