Update comments in ldconfig.c and dl-hwcaps.c.

In dl-hwcaps.c the comment read that rounding was done
to ElfW(Addr), but it's actually rounded to ElfW(Word).

In ldconfig.c we make each comment a sentence and
mention that the "tls" pseudo-hwcap is just for legacy
installations where TLS was optional.

---

2013-05-22  Carlos O'Donell  <carlos@redhat.com>

	* elf/ldconfig.c (is_hwcap_platform): Make comments full setences.
	(main): Mention "tls" pseudo-hwcap is legacy.
	* elf/dl-hwcaps.c (_dl_important_hwcaps): Correct rounding comment.