Removed the link dependency from libosd to
the Ptex library since Ptex is used only by the
examples. Updated examples/common to separate
the common Ptex sources from the other common
sources so that they are used only by the Ptex
examples.
This fixes the build when trying to build both the Metal examples
and the GL examples in the same build. The change is an unfortunate
consequence of how dependencies are bundled together in
examples/common and a future task is needed to split up these
dependencies. The same workaround exists in the DirectX examples as
well and would also benefit from splitting up the dependencies.
- changed the main OPENSUBDIV_INCLUDE_DIR to exclude ./opensubdiv
- updated CMakeLists.txt files in non-examples to use only this path
- updated CMakeLists.txt files in examples to append ./opensubdiv to path
- updated source in regression/common to use #include <opensubdiv/...>
- updated source in examples/common to use #include <opensubdiv/...>
- deferred source in examples to be updated on a case-by-case basis
