[WebAssembly] Add data size and alignement to linking section

The overal size of the data section (including BSS)
is otherwise not included in the wasm binary.

Differential Revision: https://reviews.llvm.org/D34657

llvm-svn: 306459
diff --git a/llvm/tools/obj2yaml/wasm2yaml.cpp b/llvm/tools/obj2yaml/wasm2yaml.cpp
index ad0075c..1df6afc 100644
--- a/llvm/tools/obj2yaml/wasm2yaml.cpp
+++ b/llvm/tools/obj2yaml/wasm2yaml.cpp
@@ -77,6 +77,8 @@
         LinkingSec->SymbolInfos.push_back(Info);
       }
     }
+    LinkingSec->DataSize = Obj.linkingData().DataSize;
+    LinkingSec->DataAlignment = Obj.linkingData().DataAlignment;
     CustomSec = std::move(LinkingSec);
   } else {
     CustomSec = make_unique<WasmYAML::CustomSection>(WasmSec.Name);