add vty 'no neighbors' to remove all HO targets

This is required for an upcoming TTCN3 test that plays through various neighbor
configurations.

Related: OS#4056
	 Ia4ba0e75abd3d45a3422b2525e5f938cdc5a04cc (osmo-ttcn3-hacks)
Change-Id: I8623ab581639e9f8af6a9ff1eca990518d1b1211
2 files changed