MT#55283 check return values

Change-Id: If51c8fd9c544a5b6cb7413486df10223ba979afb
Warned-by: Coverity

daemon/call.c

@@ -6164,7 +6164,8 @@ bool monologue_transform(struct call_monologue *ml, sdp_ng_flags *flags, medias_
 		if (!codec_handler_transform(m, &media->codecs))
 			return false;
 
-		__init_streams(m, NULL, flags);
+		if (!__init_streams(m, NULL, flags))
+			return false;
 	}
 
 	return true;

daemon/media_player.c

@@ -1172,7 +1172,8 @@ void media_player_set_media(struct media_player *mp, struct call_media *media) {
 	}
 	if (!mp->ssrc_out || mp->ssrc_out->h.ssrc != mp->ssrc) {
 		struct ssrc_entry_call *ssrc_ctx = get_ssrc(mp->ssrc, &media->ssrc_hash_out);
-		ssrc_ctx->next_rtcp = rtpe_now;
+		if (ssrc_ctx)
+			ssrc_ctx->next_rtcp = rtpe_now;
 		mp->ssrc_out = ssrc_ctx;
 	}
 }

daemon/rtcp.c

@@ -1313,6 +1313,8 @@ static void transcode_rr(struct rtcp_process_ctx *ctx, struct report_block *rr)
 
 	// reverse SSRC mapping
 	struct ssrc_entry_call *map_ctx = get_ssrc(ctx->scratch.rr.ssrc, &ctx->mp->media->ssrc_hash_out);
+	if (!map_ctx)
+		return;
 	rr->ssrc = htonl(map_ctx->ssrc_map_out);
 
 	if (!ctx->mp->media_out)