Link extra-libs consistently with libc and ld.so

[Roland McGrath]

> 2013-05-17  Joseph Myers  <joseph@codesourcery.com>
> 
> 	* Makefile ($(common-objpfx)linkobj/libc.so): Define
> 	link-libc-deps to empty as target-specific variable.
> 	* Makerules (link-libc-args): New variable.
> 	(libc-for-link): Likewise.
> 	(link-libc-deps): Likewise.
> 	(lib%.so): Depend in $(link-libc-deps).  Link with
> 	$(link-libc-args).

s/in/on/

> +# Target-specific variable setting:
> +$(services:%=$(objpfx)libnss_%.so) $(objpfx)libnsl.so: \
> +	libc-for-link = $(libnsl-libc)

Use two-space indentation for this case.
Otherwise it looks too similar to a target with commands.

The comment should say why it's there, not just what it is.
(The commentary was inadequate before, but this is a good time to improve it.)

> +# Target-specific variable setting:
> +$(services:%=$(objpfx)libnss_%.so): libc-for-link = $(libnss-libc)

Likewise with this comment.


Aside from those tiny cosmetic issues, this looks fine to me.


Thanks,
Roland