Don't build abi_check for crosses

[Geoff Keating]

Daniel Jacobowitz <drow@mvista.com> writes:

> This is the 3.3 version of the patch.  3.4 the test is negated and against
> GLIBCXX_IS_NATIVE:
> if test x"$GLIBCPP_IS_NATIVE" = xfalse || test x$enable_symvers = xno; then
> 
> This is necessary because automake can't build abi_check for the host. 
> Right now it's listed as a target program, and will be linked to the newly
> built libstdc++; if $build != $host or --with-cross-host, we won't be able
> to run it even if we were able to build it.  Ben, CC'd you because you
> removed the comment saying to build it native only; was there a reason?
> 
> OK?

Just because it can't be run is no reason not to double-check that it
can link...

-- 
- Geoffrey Keating <geoffk@geoffk.org>