[CMake] Switching off dependencies at compile time (with Makefiles)?

[Josef Karthauser]

I want to run nmake/make on a cmake generated build tree, but in such a
way that only the targets in the current directory get built.  That is I
want to assume that any libraries that a given project depends on (which
have separate CMakeLists.txt files) are already built, and want to
suppress nmake from attempting to build them. Is this possible?

Joe