CMake: clBLAS: fix a few missed CL_DEVICE_TYPE_GPU
CMake: clBLAS: fix a few missed CL_DEVICE_TYPE_GPU

A few samples are written in C++, we need to replace
CL_DEVICE_TYPE_GPU in them too

franz/pocl,pocl/pocl,franz/pocl,Oblomov/pocl,Oblomov/pocl,pocl/pocl,franz/pocl,pocl/pocl,franz/pocl,franz/pocl,pocl/pocl,pocl/pocl,Oblomov/pocl,Oblomov/pocl,Oblomov/pocl