spec: Only add libvirt-daemon pre install script if building with qemu

The %pre script in libvirt-daemon is specific to qemu, so only include
it if building with qemu support.

libvirt.spec.in

@@ -1524,6 +1524,7 @@ then
 fi
 
 %if %{with_libvirtd}
+    %if %{with_qemu}
 %pre daemon
         %if 0%{?fedora} >= 12 || 0%{?rhel} >= 6
 # We want soft static allocation of well-known ids, as disk images
@@ -1540,6 +1541,7 @@ if ! getent passwd qemu >/dev/null; then
 fi
 exit 0
         %endif
+    %endif
 
 %post daemon