include: legacy header files from themwi-rtp-mgr <themwi/rtp/pstn_defs.h> and <themwi/rtp/rtp_defs.h> will be populated by both the present package and themwi-rtp-mgr. Because of this duplicate definition, these two legacy headers have to be treated as essentially immutable. Why can't we drop these headers from themwi-rtp-mgr and make the present package their new (and single) official home? Answer: the present package depends on libosmocore, whereas themwi-rtp-mgr does not. We already have some programs that depend on themwi-rtp-mgr, use these headers, yet have no dependencies on Osmocom.