The 816 bytes after the 128-byte device name are the PS4
SceAutoMounterClientUsbDeviceInfo fields up to the serial length in
flatz's ps4_stub_lib_maker_v2 header: the total and available space, the
vendor id, product id and release, and the manufacturer, product and
serial strings with their lengths. libSceUsbStorage's device-info record
starts with the same layout. Every field offset is now asserted; the
size and offsets do not change.