metis: install a dynamic library

[ryandesign@…]

metis used to install a dynamic library, but this was lost when the port was updated to metis version 5 in #35018. The dynamic library should be built and installed again.

[todmorrison@…]

One line change to add "shared=1" to the "make config" line.

[cal@…]

Done in r94837. Metis should always set the CMAKE_INSTALL_NAME_DIR variable when building a shared library, because without it the resulting library contains a relative path as identifier[1], causing binaries linked against this library to be linked against a relative path[2], requiring the use of DYLD_LIBRARY_PATH and making rev-upgrade complain.

[1]

:) clemens@cSchlepptop:/opt/dports/math/metis$ otool -L /opt/local/lib/libmetis.dylib 
/opt/local/lib/libmetis.dylib:
	libmetis.dylib (compatibility version 0.0.0, current version 0.0.0)
	/usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 159.1.0)

[2]

:) clemens@cSchlepptop:/opt/dports/math/metis$ otool -L /opt/local/bin/cmpfillin 
/opt/local/bin/cmpfillin:
	libmetis.dylib (compatibility version 0.0.0, current version 0.0.0)
	/usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 159.1.0)