opencl : skip empty nodes on cgraph compute (#14491)

ggml/src/ggml-opencl/ggml-opencl.cpp

@@ -2187,7 +2187,7 @@ static ggml_status ggml_backend_opencl_graph_compute(ggml_backend_t backend, ggm
         //       dependencies.
         sync_with_other_backends(backend);
 
-        if (node->op == GGML_OP_RESHAPE || node->op == GGML_OP_TRANSPOSE || node->op == GGML_OP_VIEW || node->op == GGML_OP_PERMUTE || node->op == GGML_OP_NONE) {
+        if (ggml_is_empty(node) || node->op == GGML_OP_RESHAPE || node->op == GGML_OP_TRANSPOSE || node->op == GGML_OP_VIEW || node->op == GGML_OP_PERMUTE || node->op == GGML_OP_NONE) {
             continue;
         }