spec: fix inverted logic on sanlock

Commit d336dbdb tried to refactor sanlock to avoid building it
on RHEL for architectures where it is not available, but used
the wrong conditional.

* libvirt.spec.in (with_sanlock): Use %ifarch, not %ifnarch.

libvirt.spec.in

@@ -184,7 +184,7 @@
 %define with_sanlock 0%{!?_without_sanlock:%{server_drivers}}
 %endif
 %if 0%{?rhel} >= 6
-%ifnarch i386 i586 i686 x86_64
+%ifarch i386 i586 i686 x86_64
 %define with_sanlock 0%{!?_without_sanlock:%{server_drivers}}
 %endif
 %endif