Revert "add mDNS lookup method to libosmo-mslookup"

This reverts commit f10463c5fc6d9e786ab7c648d99f7450f9a25906, as it
causes all OBS osmo-hlr builds to fail in the mslookup_client_mdns test.

Change-Id: I5aec5b59f304c7f732c4a31131beedf29c966d9d
22 files changed