Revert "[dsymutil] MSVC does generate move constructors, but it should accept to default them"

This reverts commit r231350.

It turns out MSVC doesn't generate implicit move constructors and also doesn't accept to default them...
See for example http://lab.llvm.org:8011/builders/lldb-x86-windows-msvc/builds/2786

llvm-svn: 231351
diff --git a/llvm/tools/dsymutil/DwarfLinker.cpp b/llvm/tools/dsymutil/DwarfLinker.cpp
index e54f6bc..628643c 100644
--- a/llvm/tools/dsymutil/DwarfLinker.cpp
+++ b/llvm/tools/dsymutil/DwarfLinker.cpp
@@ -65,7 +65,10 @@
   }
 
   // Workaround MSVC not supporting implicit move ops
-  CompileUnit(CompileUnit &&RHS) = default;
+  CompileUnit(CompileUnit &&RHS)
+      : OrigUnit(RHS.OrigUnit), Info(std::move(RHS.Info)),
+        CUDie(std::move(RHS.CUDie)), StartOffset(RHS.StartOffset),
+        NextUnitOffset(RHS.NextUnitOffset) {}
 
   DWARFUnit &getOrigUnit() const { return OrigUnit; }