BSC_Tests: add testcases to verify S15-S0 handling

The handling of the AMR rate configuration bits S15-S0 is currently only
superficially checked. Lets add more some more elaborated testcases to
check through varios different situations. Also make sure that the
resulting mr configuration IE is verified

Change-Id: Ica323deb9836deea72982e093c9cb31deb5a216b
Related: SYS#4470
diff --git a/library/Osmocom_VTY_Functions.ttcn b/library/Osmocom_VTY_Functions.ttcn
index 4f795ad..fde05b3 100644
--- a/library/Osmocom_VTY_Functions.ttcn
+++ b/library/Osmocom_VTY_Functions.ttcn
@@ -90,6 +90,7 @@
 	type integer BtsNr (0..255);
 	type integer BtsTrxNr (0..255);
 	type integer BtsTimeslotNr (0..7);
+	type integer MscNr (0..255);
 
 	type charstring BtsGprsMode ("none", "gprs", "egrps");
 
@@ -118,6 +119,11 @@
 		f_vty_transceive(pt, "timeslot " & int2str(ts));
 	}
 
+	function f_vty_enter_cfg_msc(TELNETasp_PT pt, MscNr msc := 0) {
+		f_vty_enter_config(pt);
+		f_vty_transceive(pt, "msc " & int2str(msc));
+	}
+
 type record of charstring rof_charstring;
 function f_vty_config2(TELNETasp_PT pt, rof_charstring config_nodes, charstring cmd)
 {