Switch the C++ include interface in the ToolChain to use the same naming
as the system include interface before I start adding implementations of
it to individual ToolChain implementations.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@143751 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed