[PATCH] Get rid of `with_multisrctop`

[Joseph Myers]

On Fri, 8 Aug 2025, John Ericson wrote:

> +# (Now though, GNU Make is required, and GNU Make always supports VPATH.
> +# We can therefore drop support for these symlink trees. And
> +# accordingly, we can know that ${srcdir}/.. always does what we expect
> +# in all supported configurations, and use that to further simplify this
> +# multilib infrastructure. These simplifications are not yet
> +# implemented.)

Removing multisrctop support without also removing the symlink tree code 
at the same time looks like it would cause a regression.

-- 
Joseph S. Myers
josmyers@redhat.com