`cllayerinfo` is not printing anything if no layers are found

[Kerilk]

cllayerinfo does not print anything in case no layers are found, as can be seen here.

OpenCL-ICD-Loader/loader/cllayerinfo.c

Lines 125 to 130 in 9228024

	const struct KHRLayer *layer = khrFirstLayer;
	while (layer)
	{
	printLayerInfo(layer);
	layer = layer->next;
	}

cllayerinfo should print a message to report no layers were loaded, to reduce confusion.