"randrctl auto" could return the selected profile name

[drws]

Currently the randrctl auto command doesn't return anything, but I think it would be useful for it to simply return the name of the selected (matched) profile.

That also opens a question where to output information that NO matching profile was found. Should it go to the STDOUT (warning), or to the STDERR (error)? I think STDOUT is the answer, but it probably needs to be discussed.