PSFB without REMB magic word is not an error

Several PSFB messages might be supported, distinguished using
the unique identifier. If the unique identifier is not REMB, it's
not an error, and so a warning should not be issued.

Bug: webrtc:10226
Change-Id: I5e79b473bd54cf0964f19329efb33354f63f5d5e
Reviewed-on: https://webrtc-review.googlesource.com/c/118686
Reviewed-by: Danil Chapovalov <danilchap@webrtc.org>
Commit-Queue: Elad Alon <eladalon@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#26359}
diff --git a/modules/rtp_rtcp/source/rtcp_packet/remb.cc b/modules/rtp_rtcp/source/rtcp_packet/remb.cc
index 3ed1fbd..bda50f5 100644
--- a/modules/rtp_rtcp/source/rtcp_packet/remb.cc
+++ b/modules/rtp_rtcp/source/rtcp_packet/remb.cc
@@ -57,7 +57,7 @@
   }
   const uint8_t* const payload = packet.payload();
   if (kUniqueIdentifier != ByteReader<uint32_t>::ReadBigEndian(&payload[8])) {
-    RTC_LOG(LS_WARNING) << "REMB identifier not found, not a REMB packet.";
+    RTC_LOG(LS_INFO) << "REMB identifier not found, not a REMB packet.";
     return false;
   }
   uint8_t number_of_ssrcs = payload[12];