arg_validator: drop wrong default value for ArgValidatorIPRoute
arg_validator: drop wrong default value for ArgValidatorIPRoute

The parameter is not used (neither by callers not the implementation).
It also makes not sense.

Signed-off-by: Thomas Haller <16e26612e4159990a6b3691e92592e691ff74132@redhat.com>

linux-system-roles/network,linux-system-roles/network,linux-system-roles/network