Add AT_HANDLE_FID from Linux 6.5 to bits/fcntl-linux.h

[Florian Weimer]

* Joseph Myers:

> Linux 6.5 adds a constant AT_HANDLE_FID; add it to glibc.  Because
> this is a flag for the function name_to_handle_at declared in
> bits/fcntl-linux.h, put the flag there rather than alongside other
> AT_* flags in (OS-independent) fcntl.h.
>
> Tested for x86_64.
>
> diff --git a/sysdeps/unix/sysv/linux/bits/fcntl-linux.h b/sysdeps/unix/sysv/linux/bits/fcntl-linux.h
> index df378c7b89..dd9d9baf09 100644
> --- a/sysdeps/unix/sysv/linux/bits/fcntl-linux.h
> +++ b/sysdeps/unix/sysv/linux/bits/fcntl-linux.h
> @@ -368,6 +368,17 @@ struct file_handle
>  # define MAX_HANDLE_SZ	128
>  #endif
>  
> +#ifdef __USE_GNU
> +/* Flags for name_to_handle_at.  See comment in fcntl.h about the use
> +   of the same AT_* flag bits for different purposes in different
> +   functions.  */
> +# define AT_HANDLE_FID		AT_REMOVEDIR /* File handle is needed
> +						to compare object
> +						identity and may not
> +						be usable to
> +						open_by_handle_at.  */
> +#endif
> +

Looks good.  Thanks.