isisd: fix circuit is-type configuration

isisd: fix circuit is-type configuration

Currently, we have a lot of checks in CLI and NB layer to prevent
incompatible IS-types of circuits and areas. All these checks become
completely meaningless when the interface is moved between VRFs. If the
area IS-type is different in the new VRF, previously done checks mean
nothing and we still end up with incorrect circuit IS type. To actually
prevent incorrect IS type, all checks must be done in the processing
code.

Signed-off-by: Igor Ryzhov <iryzhov@nfware.com>