You just have to build last version with this option : --disable-binding-python --disable-gui-sdl --disable-samplemap --enable-avoid-float --enable-avoid-unaligned
Additional tips for this specific platform may be added. Feel free to contribute!
A binary version of navit for the Nokia n770/n800/n810 can be found here: https://garage.maemo.org/frs/?group_id=594&release_id=1703
The binary version was first created here and may be more recent that the project at maemo: http://www.tecdencia.net/navit/