zebra: show command to display metaq info

zebra: show command to display metaq info

Display below info from metaq and sub queues
1. Current queue size
2. Max/Highwater size
3. Total number of events received fo so far

r1# sh zebra metaq
MetaQ Summary
Current Size    : 0
Max Size        : 9
Total           : 20
 |------------------------------------------------------------------|
 | SubQ                             | Current  | Max Size  | Total  |
 |----------------------------------+----------+-----------+--------|
 | NHG Objects                      | 0        | 0         | 0      |
 |----------------------------------+----------+-----------+--------|
 | EVPN/VxLan Objects               | 0        | 0         | 0      |
 |----------------------------------+----------+-----------+--------|
 | Early Route Processing           | 0        | 8         | 11     |
 |----------------------------------+----------+-----------+--------|
 | Early Label Handling             | 0        | 0         | 0      |
 |----------------------------------+----------+-----------+--------|
 | Connected Routes                 | 0        | 6         | 9      |
 |----------------------------------+----------+-----------+--------|
 | Kernel Routes                    | 0        | 0         | 0      |
 |----------------------------------+----------+-----------+--------|
 | Static Routes                    | 0        | 0         | 0      |
 |----------------------------------+----------+-----------+--------|
 | RIP/OSPF/ISIS/EIGRP/NHRP Routes  | 0        | 0         | 0      |
 |----------------------------------+----------+-----------+--------|
 | BGP Routes                       | 0        | 0         | 0      |
 |----------------------------------+----------+-----------+--------|
 | Other Routes                     | 0        | 0         | 0      |
 |----------------------------------+----------+-----------+--------|
 | Graceful Restart                 | 0        | 0         | 0      |
 |------------------------------------------------------------------|

Signed-off-by: Krishnasamy <krishnasamyr@nvidia.com>