[ELF] Check linker created dynamic variables
[ELF] Check linker created dynamic variables

Check the values of _GLOBAL_OFFSET_TABLE_ and _DYNAMIC variables created by
linker.

git-svn-id: f6089bf0e6284f307027cef4f64114ee9ebb0424@221857 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/lld,llvm-mirror/lld