add f_vty_cfg_bts(), f_vty_cfg_msc()

These allow passing N vty configurations on the bts / msc node without
requiring subsequent 'exit'.

As an example, use f_vty_cfg_msc() in BSC_Tests.ttcn AMR config.

Change-Id: I9f3e485f692acb3d2a7620e9b454b372651be78e
2 files changed