[yaml2obj][ELF] Add support for st_value and st_size.

After this patch, the ELF file produced by
`yaml2obj-elf-symbol-basic.yaml`, when linked and executed on x86_64
(under SysV ABI, obviously; I tested on Linux), produces a working
executable that goes into an infinite loop!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@184469 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Object/ELFYAML.cpp b/lib/Object/ELFYAML.cpp
index 39faf7d..7fa7756 100644
--- a/lib/Object/ELFYAML.cpp
+++ b/lib/Object/ELFYAML.cpp
@@ -316,6 +316,8 @@
   IO.mapOptional("Binding", Symbol.Binding, ELFYAML::ELF_STB(0));
   IO.mapOptional("Type", Symbol.Type, ELFYAML::ELF_STT(0));
   IO.mapOptional("Section", Symbol.Section, StringRef());
+  IO.mapOptional("Value", Symbol.Value, Hex64(0));
+  IO.mapOptional("Size", Symbol.Size, Hex64(0));
 }
 
 void MappingTraits<ELFYAML::Section>::mapping(IO &IO,