Fix argument type names for images with LLVM 3.9
Fix argument type names for images with LLVM 3.9

mpflanzer/Oclgrind,mpflanzer/Oclgrind,surround-io/oclgrind,mpflanzer/Oclgrind,surround-io/oclgrind,surround-io/oclgrind,surround-io/oclgrind,mpflanzer/Oclgrind