bug#18933: ATLAS fails to build on mips

[Federico Beffa]

I'm trying to pass an architecture parameter to configure. However, if
I do something like

...
       #:configure-flags
       `(...
         ;; On non "x86_64" / "i686" platforms, do not guess processor
         ;; architecture (because it fails) and do not use ISA extensions.
         ;; We set MACHINETYPE = 52 'generic' and ISA = 1 'none'.
         ,,(if (not (and (string-prefix? "x86_64" (%current-system))
                       (string-prefix? "i686" (%current-system))))
             "-A 52 -V 1")
...

the configure flags are not recognized. Differently from this, if I
pass each parameter as a separate string as in

"-A" "52" "-V" "1"

they are recognized. Do you have a suggestion for how to achieve this
without 4 equal 'if'?

Regards,
Fede