[ObjectYAML] Support Thin MachO headers to YAML

This patch adds support to ObjectYAML for serializing mach_header structs.

llvm-svn: 269303
diff --git a/llvm/lib/ObjectYAML/CMakeLists.txt b/llvm/lib/ObjectYAML/CMakeLists.txt
index 9ebe1e3..7e1363d 100644
--- a/llvm/lib/ObjectYAML/CMakeLists.txt
+++ b/llvm/lib/ObjectYAML/CMakeLists.txt
@@ -2,4 +2,5 @@
   YAML.cpp
   COFFYAML.cpp
   ELFYAML.cpp
+  MachOYAML.cpp
   )