ran_a_channel_type_to_speech_codec_list(): set PI/PT for CSD

As per 3GPP TS 48.008, section 3.2.2.103, the Codec Type is valid if
at least one of FI, PI or PT is set to '1'.  Otherwise the Speech
Codec Element is considered invalid and shall be ignored.

Change-Id: Ibc452d37d4215c961a7946eef3ba2e7efdba078b
Related: OS#6110, OS#4394
---
M src/libmsc/ran_msg_a.c
1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/src/libmsc/ran_msg_a.c b/src/libmsc/ran_msg_a.c
index 3788805..8cf6bfa 100644
--- a/src/libmsc/ran_msg_a.c
+++ b/src/libmsc/ran_msg_a.c
@@ -1349,7 +1349,12 @@
 
 	switch (ct->ch_indctr) {
 	case GSM0808_CHAN_DATA:
-		scl->codec[0].type = GSM0808_SCT_CSD;
+		scl->codec[0] = (struct gsm0808_speech_codec) {
+			.pi = true, /* PI indicates CSDoIP is supported */
+			.pt = false, /* PT indicates CSDoTDM is not supported */
+			.type = GSM0808_SCT_CSD,
+			.cfg = 0, /* R2/R3 not set (redundancy not supported) */
+		};
 		scl->len = 1;
 		break;
 	case GSM0808_CHAN_SPEECH:

