[WebAssembly] Ensure all .debug_XXX section has proper symbol names

Updated wasm section symbols names to match section name, and ensure all
referenced sections will have a symbol (per DWARF spec v3, Figure 43)

Patch by Yury Delendik!

Differential Revision: https://reviews.llvm.org/D46543

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@331664 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed