vircgroupv2: remove ATTRIBUTE_UNUSED for used attribute

Signed-off-by: NPavel Hrdina <phrdina@redhat.com>
Acked-by: NPeter Krempa <pkrempa@redhat.com>

src/util/vircgroupv2.c

@@ -399,7 +399,7 @@ virCgroupV2EnableController(virCgroupPtr group,
 
 
 static int
-virCgroupV2MakeGroup(virCgroupPtr parent ATTRIBUTE_UNUSED,
+virCgroupV2MakeGroup(virCgroupPtr parent,
                      virCgroupPtr group,
                      bool create,
                      unsigned int flags)