When WITHOUT_CLANG is being used, also clean out the clang 3.1 headers in OptionalObsoleteFiles.inc.
When WITHOUT_CLANG is being used, also clean out the clang 3.1 headers
in OptionalObsoleteFiles.inc.

PR:		misc/169902
Submitted by:	Thomas Eberhardt <sneakywumpus@googlemail.com>
MFC after:	3 days

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase