SKip non-wrapped modules when adding dependencies to plugins.

There are cases,  e.g. the Nektar plugin, that adds modules for non-vtk-module
libraries. To handle that case, in geenral, if a module is not wrapped, we
expect the user to explicitly add dependency for that module.

Change-Id: Ia9b7c0a8748a22b9fb21b39ad323b38518264148
Merge topic '14315_fix_plugin_cs_wrappings' into next

fcf8fdd SKip non-wrapped modules when adding dependencies to plugins.