r367672 broke the NFS server

Hi,

Post r367671...
When multiple files are being created by an NFS client in the same
directory, the VOP_CREATE()/ufs_create() can fail with ERELOOKUP.
This results in a EIO return to the NFS client.
--> This causes "nfsv4 client/server protocol prob err=10026"
      on the client for NFSv4.0 mounts.
      --> This explains why this error has been reported by
            several people lately, although it should "never happen".

Unfortunately, for the NFS server, the Lookup call is done separately
and it will not be easy to redo it, given the current NFS code structure.

Is there another way to deal with the problem r367672 was fixing that
avoids ufs_create() returning ERELOOKUP?

rick