Accepting request 150534 from Base:System

- looks like testsuite runs only on kvm, so add _constraint
  (actually it does not build on xen, but I can't constraint that) (forwarded request 150519 from coolo)

OBS-URL: https://build.opensuse.org/request/show/150534
OBS-URL: https://build.opensuse.org/package/show/openSUSE:Factory/glibc?expand=0&rev=138

_constraints

@@ -5,4 +5,5 @@
       <size unit="M">1500</size>
     </memory>
   </hardware>
+  <sandbox>kvm</sandbox>
 </constraints>