[ppc] Include hwcap as ifunc argument

[David Miller]

From: Richard Henderson <rth@twiddle.net>
Date: Mon, 21 May 2012 09:58:50 -0700

> Dave, dunno if you wanna change the signature of the arg from int to
> unsigned long for 64-bit?  It just seemed prudent to do that here...

I don't think so, because I'll always have to accomodate 32-bit
userland running on a 64-bit kernel, and thus I'll effectively always
be limited to 32-bit hwcap values.

So I'd rather not create the illusion that something larger than
32-bit is even possible. :-)

And on this topic I frankly think, as I did when I made the original
sparc change, that we should pass the hwcaps into the IFUNC resolvers
on every target not just a select few.