C++17 compatibility: unreachable break.

(For some reason, clang seems to find more things like this when in
C++17 mode.)

Bug: 111067277
Test: builds
Change-Id: Ic76b4061df742fe968f2d5ef3b62590d4da92c22
diff --git a/command_processor.cpp b/command_processor.cpp
index ea223af..e96bd3d 100644
--- a/command_processor.cpp
+++ b/command_processor.cpp
@@ -229,7 +229,6 @@
         break;
       case Opcode::kDumpBuffers:
         LOG(FATAL) << "Unexpected DumpBuffers command in log";
-        break;
     }
     output_string += '\n';