* opencl: allow multiple workgroups for large rows * opencl: improve small cpy * opencl: packed concat for small input * opencl: tweak flat q6_K gemv, increase N_DST and remap threads
* opencl: allow multiple workgroups for large rows * opencl: improve small cpy * opencl: packed concat for small input * opencl: tweak flat q6_K gemv, increase N_DST and remap threads