acl: Fix acl_remove not to mess up the ACL

It leaks memory and fails to adjust qemu_acl member nentries.  Future
acl_add become confused: can misreport the position, and can silently
fail to add.

Cc: qemu-stable@nongnu.org
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

util/acl.c

@@ -168,6 +168,9 @@ int qemu_acl_remove(qemu_acl *acl,
         i++;
         if (strcmp(entry->match, match) == 0) {
             QTAILQ_REMOVE(&acl->entries, entry, next);
+            acl->nentries--;
+            g_free(entry->match);
+            g_free(entry);
             return i;
         }
     }