Close the gap between ELF and COFF ICF implementations. NFC.
Close the gap between ELF and COFF ICF implementations. NFC.

We originally wrote the ICF code for COFF and ported it to ELF.
They started diverging since then. This patch closes the gap.

git-svn-id: f6089bf0e6284f307027cef4f64114ee9ebb0424@303801 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/lld,llvm-mirror/lld