Fixed libclang link list to be just libnames, which are then given to POCL_PRIVATE_LINK_LIST
Removed duplicate link flags and fixed LLVM_SYSLIBS to be linked with target_link_libraries() which works also with windows build.
Fixed compiling examples c++ compiler.
Added hardcoded target type for windows.

MicrosoftCXXMangler does not support yet mangling extended vector types.