ocfs2: reserve xattr block for new directory with inline data

If this is a new directory with inline data, we choose to
reserve the entire inline area for directory contents and
force an external xattr block.

Signed-off-by: Tiger Yang <tiger.yang@oracle.com>
Acked-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>