ssha-opencl: Check device max allocation size.
Make use of mem_calloc() in a bunch of GPU formats. Also change some
mem_alloc_tiny to mem_alloc and add MEM_FREE() in done().
Merge branch 'unstable-jumbo' into bleeding-jumbo

* unstable-jumbo:
  Make use of mem_calloc() in a bunch of GPU formats. Also change some mem_alloc_tiny to mem_alloc and add MEM_FREE() in done().
  ssha-opencl: Check device max allocation size.