[PATCH] aarch64: add support or hwcap3,4

[Florian Weimer]

* Yury Khrustalev:

> On Tue, Apr 01, 2025 at 04:50:51PM +0200, Florian Weimer wrote:
>> * Yury Khrustalev:
>> 
>> > This is just to ensure both hwcap3,4 are usable on AArch64 targets.
>> 
>> Is there an AT_HWCAP or AT_HWCAP2 bit that indicates the additional
>> arguments are available?
>
> No, there is no such bit.

Ah, right, this is expected to be handled through the _size member.
Maybe expand the comments in <sys/ifunc.h> a bit to explains this?

Thanks,
Florian