the block to read and copy out. This removes the hack in
udf_readatoffset() for only reading one block at a time. WooHoo!
Remove a redundant test for fragmented fids in both udf_readdir()
and udf_lookup(). Add comment to both as to why the test is
written the way it is. Add a few more safety checks for brelse().
Thanks to Timothy Shimmin <tes@boing.melbourne.sgi.com> for pointing
out these problems.