Add AGROUP from Linux 5.19 to sys/acct.h, remove Alpha version (bug 29502)

[Florian Weimer]

* Joseph Myers:

> Linux 5.19 adds a new accounting flag AGROUP; add it to the
> enumeration in sys/acct.h.
>
> This shows up that the Alpha-specific variant of this header has a
> different set of constants and struct acct, which appear to be the
> constants and structure layout from Linux 2.0.  These were changed
> some time between Linux 2.0 and Linux 2.2; I see no evidence of an
> Alpha-specific layout or set of constants, but haven't checked the
> detailed Linux kernel history between those versions.  Rather, it
> looks like tha Alpha-specific header was originally needed because of
> the use of types in the kernel structure (such as uid_t and gid_t)
> that had different sizes on Alpha, and when glibc was updated for
> changes to the structure and constants in the kernel
>
> 1998-10-02  Andreas Jaeger  <aj@arthur.rhein-neckar.de>
>
>         * sysdeps/unix/sysv/linux/sys/acct.h: Bring in sync with current
>         linux 2.1 version.
>
> that simply omitted to do anything about the Alpha version.
>
> Thus, remove the Alpha version in order to get the updated definitions
> into use on Alpha, as I don't think the interfaces are actually
> different for Alpha with any kernel version supported by glibc.
>
> Tested for x86_64, and with build-many-glibcs.py for alpha-linux-gnu.

Constant matches kernel.  Alpha change looks okay to me.

Reviewed-by: Florian Weimer <fweimer@redhat.com>

Thanks,
Florian