When issuing an ioctl for a file that exists in a FAT32 file system, the FAT ioctl() is first executed, but it returns -ENOSYS in an attempt to pass through to the vfs. Therefore, the ioctl of the VFS layer, which expects -ENOTTY, is not processed and an error occurs. Signed-off-by: Takeyoshi Kikuchi <kikuchi@centurysys.co.jp>