test if possible

[Roland McGrath]

> There hasn't been a Binutils release yet which contains the required
> feature.  The first version will be 2.21.1.  Building glibc 2.14 for
> S/390 will require this version.

I see.  I presume the feature is in current binutils, there just hasn't
been a GNU release.  So plenty of people might actually have an adequate
assembler.  The right thing to do regardless is to write a functional
configure check in sysdeps/s390/configure(.in) (or a more-specific
directory if only there is where the feature is required) that checks for
an assembler capable of handling the code.


Thanks,
Roland