Use union and correct types in clGetKernelArgInfo.
Use union and correct types in clGetKernelArgInfo.

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