Introduce arch-specific checker tests.

- The '.cfg' output is now created on target.
- Arch-specific checker tests can be created by inserting a
  suffix. For example:
      /// CHECK-START-ARM64: int Main.foo(int) register (after)
      /// CHECK-DAG:   <<Arg:i\d+>>     ParameterValue

Change-Id: I55cdb37f8e806c7ffdde6b676c8f44ac30b59051
diff --git a/disassembler/disassembler_arm64.cc b/disassembler/disassembler_arm64.cc
index 348b2a5..5f88714 100644
--- a/disassembler/disassembler_arm64.cc
+++ b/disassembler/disassembler_arm64.cc
@@ -94,7 +94,7 @@
     int64_t offset = instr->ImmLSUnsigned() << instr->SizeLS();
     std::ostringstream tmp_stream;
     Thread::DumpThreadOffset<8>(tmp_stream, static_cast<uint32_t>(offset));
-    AppendToOutput(" (%s)", tmp_stream.str().c_str());
+    AppendToOutput(" ; %s", tmp_stream.str().c_str());
   }
 }