[Pkg-opencl-devel] opencl-icd selection

[Rebecca N. Palmer]

In addition to the already-noted problems (we're trying to get a 
matching-the-hardware ordering, not a consistent ordering), renaming 
package-provided files is likely to confuse the package management 
system, so probably isn't something we want to encourage.

As the discrete GPU is likely to be faster than the integrated GPU on 
systems with both, I'd suggest sorting nvidia, mesa, beignet if we find 
more than one platform with a GPU device.