intel: Mark an otherwise unused variable in intel_dump_gpu as ASSERTED

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/9862>

src/intel/tools/intel_dump_gpu.c

@@ -480,7 +480,7 @@ maybe_init(int fd)
    bos = calloc(MAX_FD_COUNT * MAX_BO_COUNT, sizeof(bos[0]));
    fail_if(bos == NULL, "out of memory\n");
 
-   int ret = get_pci_id(fd, &device);
+   ASSERTED int ret = get_pci_id(fd, &device);
    assert(ret == 0);
 
    aub_file_init(&aub_file, output_file,