tipc: add link monitor list

tipc: add link monitor list

In this commit, we list the monitor attributes. By default it lists
the attributes for all bearers, otherwise the specified bearer.

A sample usage is shown below:
$ tipc link monitor list

bearer eth:data0
node          status monitored generation applied_node_status [non_applied_node:status]
1.1.1         up     direct    16         UU []
1.1.2         up     direct    16         UU []
1.1.3         up     direct    16         UU []

bearer eth:data1
node          status monitored generation applied_node_status [non_applied_node:status]
1.1.1         up     direct    2          UU []
1.1.2         up     direct    3          UU []
1.1.3         up     direct    3          UU []

$ tipc link monitor list media eth device data0

bearer eth:data0
node          status monitored generation applied_node_status [non_applied_node:status]
1.1.1         up     direct    16         UU []
1.1.2         up     direct    16         UU []
1.1.3         up     direct    16         UU []

$ tipc link monitor list -h
Usage: tipc monitor list [ media MEDIA ARGS...]

MEDIA
 udp                   - User Datagram Protocol
 ib                    - Infiniband
 eth                   - Ethernet

Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Tested-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>