SUNRPC: Fix tcp reconnection

This fixes a problem that was reported as Red Hat Bugzilla entry number
485339, in which rpciod starts looping on the TCP connection code,
rendering the NFS client unusable for 1/2 minute or so.

It is basically a backport of commit
f75e6745aa3084124ae1434fd7629853bdaf6798 (SUNRPC: Fix the problem of
EADDRNOTAVAIL syslog floods on reconnect)

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>