cad/calculix-ccx math/arpack++ math/armadillo math/scilab math/octave: Change dependency from math/arpack to math/arpack-ng

math/arpack is a dead, unmaintained project, and math/arpack-ng is a maintained and updated fork.
This commit is effectively a version upgrade of the arpack dependency.

Approved by: portmgr blanket (does not result in a change in contents of the resulting package)