Massive removal of unused code/structs/headers

osmo-msc still had large amounts of dead code that came along from
openbsc.git.  This commit removes a lot of it, mostly stuff relevant
only to the BSC side of things (or even GPRS).

Change-Id: I247def85da2dc3ec461389fb74414a0d964e7e3c
Related: OS#2528
diff --git a/src/libmsc/vty_interface_layer3.c b/src/libmsc/vty_interface_layer3.c
index dbd826d..f8fc098 100644
--- a/src/libmsc/vty_interface_layer3.c
+++ b/src/libmsc/vty_interface_layer3.c
@@ -35,8 +35,6 @@
 #include <osmocom/msc/gsm_subscriber.h>
 #include <osmocom/msc/silent_call.h>
 #include <osmocom/msc/gsm_04_11.h>
-#include <osmocom/abis/e1_input.h>
-#include <osmocom/msc/abis_nm.h>
 #include <osmocom/gsm/gsm_utils.h>
 #include <osmocom/core/utils.h>
 #include <osmocom/msc/db.h>
@@ -46,10 +44,9 @@
 #include <osmocom/msc/vty.h>
 #include <osmocom/msc/gsm_04_80.h>
 #include <osmocom/msc/gsm_04_14.h>
-#include <osmocom/msc/chan_alloc.h>
+#include <osmocom/gsm/protocol/gsm_08_58.h>
 #include <osmocom/msc/sms_queue.h>
 #include <osmocom/msc/mncc_int.h>
-#include <osmocom/msc/handover.h>
 #include <osmocom/msc/vlr.h>
 
 #include <osmocom/vty/logging.h>