CMake: add DEAL_II_CGAL_HAS_DEPRECATED_BOOST_INCLUDES check

[tamiko]

It is back:

In file included from /usr/include/boost/smart_ptr/detail/sp_thread_sleep.hpp:22,
                 from /usr/include/boost/smart_ptr/detail/yield_k.hpp:23,
                 from /usr/include/boost/smart_ptr/detail/spinlock_gcc_atomic.hpp:14,
                 from /usr/include/boost/smart_ptr/detail/spinlock.hpp:42,
                 from /usr/include/boost/smart_ptr/detail/spinlock_pool.hpp:25,
                 from /usr/include/boost/smart_ptr/shared_ptr.hpp:29,
                 from /usr/include/boost/property_map/vector_property_map.hpp:14,
                 from /usr/include/boost/property_map/property_map.hpp:606,
                 from /usr/include/CGAL/property_map.h:19,
                 from /usr/include/CGAL/boost/graph/properties.h:16,
                 from /usr/include/CGAL/boost/graph/helpers.h:16,
                 from /usr/include/CGAL/Polygon_mesh_processing/measure.h:22,
                 from test.cc:10:
/usr/include/boost/iterator.hpp:10:1: note: ‘#pragma message: This header is deprecated. Use <iterator> instead.’
   10 | BOOST_HEADER_DEPRECATED("<iterator>")

In order to work around the newest set of deprecated header warnings (this
time triggered by CGAL including a deprecated header :-(() I would
otherwise have to add this "#define dance" at various other places.

Instead, it is cleaner to simply give up and define the macro globally.

The configure checks will ensure that the macro is only ever defined if
needed.

In reference to #13910

[luca-heltai]

/rebuild