CIF to mCRL2 transformation gives an incorrect warning when disabling default value actions

When you use the CIF to mCRL2 transformation on a specification which contains variables with the read-values option set to "-*", it gives the following warning:

WARNING: Value actions option pattern "-*" does not make any change to the selected variables. Matched variables were never added or already removed earlier.

This is not correct, as the pattern "-*" removes all variables from the selection, and by default all variables are selected. So the pattern does change the selected variables.