Revert "mgcp_client: don't configure "bts base"" until osmo-msc is ready

OsmoMSC is in the odd situation that it is already using the new 
libosmo-mgcp-client, which is targeted at osmo-mgw, to configure talking to the
old osmo-bsc_mgcp. By removing the bts_base, we break current OsmoMSC.

Removing bts_base makes sense, but let's revert this until OsmoMSC is ready
after merging Ieea9630358b3963261fa1993cf1f3b563ff23538 (which moves the 
osmo-msc over to osmo-mgw).

This reverts commit 0be3ce66c058f39e07f7a1c93a9bf632fb936edf.

Change-Id: Ibce214c2bfc35623097abbb647619426ef3dcc94
3 files changed