clGetPlatformIDs return value fix
It should return CL_SUCCESS in case num_platforms == NULL && num_entries
== 0.  At least Glow checks for availability of OpenCL (in general)
using these parameters.
Specs say:
"If platforms is not NULL, the num_entries must be greater than zero."
@@ -251,7 +251,7 @@ POname(clGetPlatformIDs)(cl_uint num_entries,
CL_INVALID_VALUE);
POCL_RETURN_ERROR_COND ((num_platforms == NULL && num_entries == 0),
- CL_INVALID_VALUE);
+ CL_SUCCESS);
if (platforms != NULL) {
platforms[0] = &_platforms[0];
