The implementation will use some default in this case. The empty string
is not a meaningful device for any existing hardware type, and indeed
OpenCL treats it identically to no device already to work around the lack
of this setting on the command line.
* commit 'c95169f0ec68bdeeabc5fde8aa4076f406242524':
build: Move cli tool sources to a separate subdirectory
Merged-by: James Almer <jamrial@gmail.com>