netlink: Rename pid to portid to avoid confusion

It is a frequent mistake to confuse the netlink port identifier with a
process identifier.  Try to reduce this confusion by renaming fields
that hold port identifiers portid instead of pid.

I have carefully avoided changing the structures exported to
userspace to avoid changing the userspace API.

I have successfully built an allyesconfig kernel with this change.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/openvswitch/vport.c b/net/openvswitch/vport.c
index 1abd960..9055dd6 100644
--- a/net/openvswitch/vport.c
+++ b/net/openvswitch/vport.c
@@ -125,7 +125,7 @@
 
 	vport->dp = parms->dp;
 	vport->port_no = parms->port_no;
-	vport->upcall_pid = parms->upcall_pid;
+	vport->upcall_portid = parms->upcall_portid;
 	vport->ops = ops;
 	INIT_HLIST_NODE(&vport->dp_hash_node);