AudioFlinger: Move RecordBufferConverter to libaudioprocessing

Test: Recording loopback
Bug: 31015569
Change-Id: I7897d959f36ac7424544e35f47576c99a442dd54
diff --git a/services/audioflinger/AudioFlinger.h b/services/audioflinger/AudioFlinger.h
index 35eceb2..e97d1ed 100644
--- a/services/audioflinger/AudioFlinger.h
+++ b/services/audioflinger/AudioFlinger.h
@@ -80,6 +80,7 @@
 class EffectsFactoryHalInterface;
 class FastMixer;
 class PassthruBufferProvider;
+class RecordBufferConverter;
 class ServerProxy;
 
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