[LITE][OPENCL][Image] 1x1 suite relu6 (#2979)

lite/backends/opencl/cl_kernel/image/conv2d_1x1_kernel.cl

@@ -191,12 +191,10 @@ __kernel void conv2d_1x1(__private const int global_size_dim0,
             READ_IMG_TYPE(CL_DTYPE_CHAR, new_biase, sampler, (int2)(out_c, 0));
 #endif
 
-#ifdef RELU
   output0 = activation_type4(output0);
   output1 = activation_type4(output1);
   output2 = activation_type4(output2);
   output3 = activation_type4(output3);
-#endif
 
   if (out_w0 < old_w) {
     WRITE_IMG_TYPE(CL_DTYPE_CHAR, output_image, output_pos0, output0);