[ELF] - Ignore -plugin-opt=-function-sections/-plugin-opt=-data-sections. NFC.
[ELF] - Ignore -plugin-opt=-function-sections/-plugin-opt=-data-sections. NFC.

Clang passes this options to linker. We should ignore them,
anyways they are always enabled by default atm.

Fixes https://bugs.llvm.org/show_bug.cgi?id=34200.

git-svn-id: f6089bf0e6284f307027cef4f64114ee9ebb0424@310995 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/lld,llvm-mirror/lld