This patch fixes how the NFS client handles full NFS version 3 64-bit fileids.

Previously, messages of the form:
NFS3 LOOKUP: directory attributes from <servername> are of the wrong dir

would appear on the console when traversing an NFS version 3 server filesystem
that generated greater than 32-bit file ids.  This patch stores the full 64-bit
fileid (as specified by protocol) and uses that actual value to compare.

This patch also fixes an underlying problem in the NFS client that could lead 
to a panic on a single system or an assertion failure panic on a cluster.

These conditions would be triggered by the temporary existence of two vnodes
for the same mount/file handle combination.

This patch also fixes a possible race with m_freem() and clntkudp_destroy 
which could lead to a mixed up mbuf chain.

Change to the NFS client to decouple it from the networking driver's
processing, specifically from the delay to free transmitted buffers.

Adds a lock to the initialization of a private client to avoid hung 
file system threads when the MVFS ClearCase filesystem is in use.


