Replace mount-options with mount where appropriate.

Since our minimum supported version is now 1.16 and mount was fixed in
1.13.16, it is now safe to replace mount-options + empty options with
mount wherever it occurs.

java/examples/CreateDisk.java

@@ -54,7 +54,7 @@ public class CreateDisk
             g.mkfs ("ext4", partitions[0]);
 
             // Now mount the filesystem so that we can add files.
-            g.mount_options ("", partitions[0], "/");
+            g.mount (partitions[0], "/");
 
             // Create some files and directories.
             g.touch ("/empty");