Allow clang to be installed in c:\LLVM on win32 64 bit builds. [ci skip]
Allow clang to be installed in c:\LLVM on win32 64 bit builds. [ci skip]

timfel/squeakvm,timfel/squeakvm,timfel/squeakvm,timfel/squeakvm,timfel/squeakvm,timfel/squeakvm,timfel/squeakvm,timfel/squeakvm