AEC dump Stream::level renamed

Making it clear that the field is used to store the applied input
volume and not the recommended input volume.

Bug: webrtc:7494, b/241923537
Change-Id: Ib91bc1a12348f63e3a4ba6e068ed02e40786a87b
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/271342
Reviewed-by: Jesus de Vicente Pena <devicentepena@webrtc.org>
Commit-Queue: Alessio Bazzica <alessiob@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#38051}

modules/audio_processing/include/aec_dump.h

@@ -67,7 +67,7 @@ class AecDump {
   struct AudioProcessingState {
     int delay;
     int drift;
-    int level;
+    int applied_input_volume;
     bool keypress;
   };