drop gsm48 RR ciph mode compl from permitted initial messages

It is a message that is initially permitted, but it is in fact not handled in
the L3 code but already before, upon receiving
BSS_MAP_MSG_CIPHER_MODE_COMPLETE.

Change-Id: I0079f07271ca76bd457d0e700f3a736eb9066b47
diff --git a/src/libmsc/gsm_04_08.c b/src/libmsc/gsm_04_08.c
index 2962760..95c3183 100644
--- a/src/libmsc/gsm_04_08.c
+++ b/src/libmsc/gsm_04_08.c
@@ -1296,7 +1296,8 @@
 		break;
 	case GSM48_PDISC_RR:
 		switch (msg_type) {
-		case GSM48_MT_RR_CIPH_M_COMPL:
+		/* GSM48_MT_RR_CIPH_M_COMPL is actually handled in bssmap_rx_ciph_compl() and gets redirected in the
+		 * BSSAP layer to ran_conn_cipher_mode_compl() (before this here is reached) */
 		case GSM48_MT_RR_PAG_RESP:
 			return true;
 		default: