Deprecate odl-restconf-noauth feature

odl-restconf-noauth feature is just a historic relic. It does not really
have any usage and odl-restconf should be use instead (this has the same
functionality but with authentication).

Deprecate odl-restconf-noauth feature.

Change-Id: I5007a0318f75415ecbbec4ea02e123f8f6b35324
Signed-off-by: Jakub Morvay <jmorvay@frinx.io>