set rtp_has_crypto for dtls calls

src/switch_rtp.c

@@ -3379,6 +3379,7 @@ SWITCH_DECLARE(switch_status_t) switch_rtp_add_crypto_key(switch_rtp_t *rtp_sess
 	if (switch_event_create(&fsevent, SWITCH_EVENT_CALL_SECURE) == SWITCH_STATUS_SUCCESS) {
 		if (rtp_session->dtls) {
 			switch_event_add_header(fsevent, SWITCH_STACK_BOTTOM, "secure_type", "srtp:dtls:AES_CM_128_HMAC_SHA1_80");
+			switch_channel_set_variable(channel, "rtp_has_crypto", "srtp:dtls:AES_CM_128_HMAC_SHA1_80");
 		} else {
 			switch_event_add_header(fsevent, SWITCH_STACK_BOTTOM, "secure_type", "srtp:sdes:%s", switch_channel_get_variable(channel, "rtp_has_crypto"));
 		}