Basically you have 2 options with or without X11. Now for some reason beyond my understadning this is not a switch thrown in at compile time but you need to specify a dedicated port build for either with or without X11.
To build open vm tools without X11 use the following port and install method.
cd /usr/ports/emulators/open-vm-tools-nox11 && make install clean
To build open vm tools with X11 use the following port and install method.
cd /usr/ports/emulators/open-vm-tools && make install clean