[libunwind][NFC] Suppress unused parameter warnings

Reviewers: EricWF

Subscribers: christof, chrib, dexonsmith, cfe-commits

Differential Revision: https://reviews.llvm.org/D52393

git-svn-id: https://llvm.org/svn/llvm-project/libunwind/trunk@342811 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed