Use AudioProcessingBuilder everywhere AudioProcessing is created.

The AudioProcessingBuilder was recently introduced in https://webrtc-review.googlesource.com/c/src/+/34651 to make it easier to create APM instances. This CL replaces all calls to the old Create methods with the new AudioProcessingBuilder.

Bug: webrtc:8668
Change-Id: Ibb5f0fc0dbcc85fcf3355b01bec916f20fe0eb67
Reviewed-on: https://webrtc-review.googlesource.com/36082
Commit-Queue: Ivo Creusen <ivoc@webrtc.org>
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#21534}

modules/audio_processing/include/audio_processing.h

@@ -112,7 +112,7 @@ struct DelayAgnostic {
 // microphone volume is set too low. The value is clamped to its operating range
 // [12, 255]. Here, 255 maps to 100%.
 //
-// Must be provided through AudioProcessing::Create(Confg&).
+// Must be provided through AudioProcessingBuilder().Create(config).
 #if defined(WEBRTC_CHROMIUM_BUILD)
 static const int kAgcStartupMinVolume = 85;
 #else
@@ -205,7 +205,7 @@ struct Intelligibility {
 // data.
 //
 // Usage example, omitting error checking:
-// AudioProcessing* apm = AudioProcessing::Create(0);
+// AudioProcessing* apm = AudioProcessingBuilder().Create();
 //
 // AudioProcessing::Config config;
 // config.level_controller.enabled = true;