[NFC] Mark LWG3128 and LWG3132 as requiring no work

Those LWG issues were adopted in San Diego and require no work
on our side.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@346799 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed