audioflinger: Dump software patches

Example output:

    Software patches:
      Patch 44: thread 0xa6d83900 => thread 0xa7dfe000

This helps to identify threads used for the patch.

Test: adb shell dumpsys media.audio_flinger
Change-Id: I6c70945abd8e4abd46cd0311559d35efb6127555
diff --git a/services/audioflinger/AudioFlinger.cpp b/services/audioflinger/AudioFlinger.cpp
index 306d1a1..7068377 100644
--- a/services/audioflinger/AudioFlinger.cpp
+++ b/services/audioflinger/AudioFlinger.cpp
@@ -533,6 +533,8 @@
             dev->dump(fd);
         }
 
+        mPatchPanel.dump(fd);
+
 #ifdef TEE_SINK
         // dump the serially shared record tee sink
         if (mRecordTeeSource != 0) {