[PECOFF] Fix XML output bug.
[PECOFF] Fix XML output bug.

We really need a test for the manifest file output, but because it depends
on external commands (CVTRES.EXE and RC.EXE), it's not very easy to write it.

git-svn-id: f6089bf0e6284f307027cef4f64114ee9ebb0424@193445 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/lld,llvm-mirror/lld