[llvm] [DirectX] Add ObjectFile boilerplate for objdump (PR #151434)

[Fangrui Song via llvm-commits]

================
@@ -0,0 +1,30 @@
+//===-- DXContainerDump.cpp -----------------------------------------------===//
----------------
MaskRay wrote:

`//===----------------------------------------------------------------------===//`

https://github.com/llvm/llvm-project/pull/151434