Clean-up: Move some macros that are specific to the Van Jacobson
implementation into xprt.c. Get rid of the cong_wait field in
rpc_xprt, which is no longer used. Get rid of xprt_clear_backlog.
Test-plan:
Compile with CONFIG_NFS enabled.
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>