audio: fix switch to break or use FALLTHROUGH_INTENDED

Test: compile, sanity
Bug: 117509050
Change-Id: I9439f201b3d1f4485ab698d7bed063a02f17f8f0
diff --git a/media/libnblog/Merger.cpp b/media/libnblog/Merger.cpp
index 30f6fe3..3ad6d6b 100644
--- a/media/libnblog/Merger.cpp
+++ b/media/libnblog/Merger.cpp
@@ -188,6 +188,7 @@
         case EVENT_RESERVED:
         case EVENT_UPPER_BOUND:
             ALOGW("warning: unexpected event %d", it->type);
+            break;
         default:
             break;
         }