Allow configuring DSCP on controller and manager connections.

Allow configuring DSCP on controller and manager connections.

The changes allow the user to specify a separate dscp value for the
controller connection and the manager connection. The value will take
effect on resetting the connections. If no value is specified a default
value of 192 is chosen for each of the connections.

Feature #10074
Requested-by: Rajiv Ramanathan <rramanathan@nicira.com>
Signed-off-by: Mehak Mahajan <mmahajan@nicira.com>