mgcp: use osmo-mgw to switch rtp streams

in the current implementation we still use osmo-bsc_mgcp, which
has many problems and is also obsoleted by osmo-mgw.

integrate osmo-mgw and re-implement the current switching using
an osmo fsm.

Depends: osmo-mgw Iab6a6038e7610c62f34e642cd49c93d11151252c
Depends: osmo-iuh I3c1a0455c5f25cae41ee19229d6daf299e023062
Closes: OS#2605
Change-Id: Ieea9630358b3963261fa1993cf1f3b563ff23538
diff --git a/src/libmsc/Makefile.am b/src/libmsc/Makefile.am
index 8ae0e18..91d1854 100644
--- a/src/libmsc/Makefile.am
+++ b/src/libmsc/Makefile.am
@@ -39,6 +39,7 @@
 	mncc_builtin.c \
 	mncc_sock.c \
 	msc_ifaces.c \
+	msc_mgcp.c \
 	rrlp.c \
 	silent_call.c \
 	sms_queue.c \