Change YAML traits for vector<string> to flow_vector.

This is a workaround for an ODR conflict with the definition in
AMDGPUCodeObjectMetadata.cpp.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305584 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed