This patch takes the BKL out of vfs_readdir() and moves it into the
individual filesystems, all 35 of them.  I have the feeling that this
wasn't done before because there are a lot of these to change and it was
a pain to find them all.  I definitely got all of those that were
defined in the in the structure declaration like this "readdir:
fs_readdir;" vxfs_readdir was assigned strangely, but I found it anyway.
I also left devfs out of this one.  Richard seems confident that devfs
has no need for the BKL.