ocfs2: Reserve ioctl range

We need to reserve at least two ioctls for online-resize. Reserve a small
range of ioctls for Ocfs2 use in Documentation/ioctl-number.txt. This should
give us enough room for future growth.

Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>