commonfns: test_unary_fn returns CL_DEVICE_NOT_FOUND on verification failure instead of appropriate error

[funch0za]

In the commonfs test, the test_unary_fn test case returns -1 if the calculated values are not equal to the reference values.
Excerpt from the test_unary_fn test case:

if (verifyFn((T *)&input_ptr.front(), (T *)&output_ptr.front(),                                                                            
                     n_elems * (i + 1)))                                                                                                           
        {                                                                                                                                          
            log_error("%s %s%d test failed\n", fnName.c_str(), tname.c_str(),                                                                      
                      ((g_arrVecSizes[i])));                                                                                                       
            err = -1;                                                                                                                              
        }

The -1 code corresponds to CL_DEVICE_NOT_FOUND.
Maybe in this case, you need to change the error code to another one? CL_DEVICE_NOT_FOUND may be misleading.