Fix a layout pass debug message.

git-svn-id: https://llvm.org/svn/llvm-project/lld/trunk@192942 91177308-0d34-0410-b5e6-96231b3b80d8
Fix -Wunused-function warning of release build.

git-svn-id: https://llvm.org/svn/llvm-project/lld/trunk@192943 91177308-0d34-0410-b5e6-96231b3b80d8