xen/tmem: Add missing %s in the printk statement.

Seems that it got lost.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
diff --git a/drivers/xen/tmem.c b/drivers/xen/tmem.c
index 144564e..3ee836d 100644
--- a/drivers/xen/tmem.c
+++ b/drivers/xen/tmem.c
@@ -385,7 +385,7 @@
 		if (old_ops.init != NULL)
 			s = " (WARNING: frontswap_ops overridden)";
 		printk(KERN_INFO "frontswap enabled, RAM provided by "
-				 "Xen Transcendent Memory\n");
+				 "Xen Transcendent Memory%s\n", s);
 	}
 #endif
 #ifdef CONFIG_CLEANCACHE