[show] Enhance show interface status command output

[rvisnu]

- What I did
I have added neighbour device and neighbour device's port info output at the end of the "show interface status" command. Resolved comments from Previous PR : https://github.com/Azure/sonic-utilities/pull/590 which was closed due to merge conflict issues
- How I did it
I did this by getting the neighbour info from the CONFIG DB
- How to verify it
Verified using the lab test machine
- Previous command output (if the output of a command-line utility has changed)

    Interface            Lanes    Speed    MTU           Alias           Vlan    Oper    Admin    Type    Asym PFC 
-------------  ---------------  -------  -----  --------------  -------------  ------  -------  ------  ---------- 
  Ethernet100  125,126,127,128      40G   9100  fortyGigE0/100         routed    down     down   QSFP+         off 
  Ethernet104      85,86,87,88      40G   9100  fortyGigE0/104         routed    down     down   QSFP+         off 
  Ethernet108      81,82,83,84      40G   9100  fortyGigE0/108         routed    down     down   QSFP+         off 
  Ethernet112      89,90,91,92      40G   9100  fortyGigE0/112  PortChannel01      up       up   QSFP+         off 
  Ethernet116      93,94,95,96      40G   9100  fortyGigE0/116  PortChannel02      up       up   QSFP+         off 
  Ethernet120     97,98,99,100      40G   9100  fortyGigE0/120  PortChannel03      up       up   QSFP+         off 
  Ethernet124  101,102,103,104      40G   9100  fortyGigE0/124  PortChannel04      up       up   QSFP+         off 
PortChannel01              N/A      40G   9100             N/A         routed    down       up     N/A         N/A
PortChannel02              N/A      40G   9100             N/A         routed    down       up     N/A         N/A
PortChannel03              N/A      40G   9100             N/A         routed    down       up     N/A         N/A
PortChannel04              N/A      40G   9100             N/A         routed    down       up     N/A         N/A

- New command output (if the output of a command-line utility has changed)

    Interface            Lanes    Speed    MTU           Alias           Vlan    Oper    Admin    Type    Asym PFC    Neighbour         Port
-------------  ---------------  -------  -----  --------------  -------------  ------  -------  ------  ----------  -----------  -----------
  Ethernet100  125,126,127,128      40G   9100  fortyGigE0/100         routed    down     down   QSFP+         off          N/A          N/A
  Ethernet104      85,86,87,88      40G   9100  fortyGigE0/104         routed    down     down   QSFP+         off          N/A          N/A
  Ethernet108      81,82,83,84      40G   9100  fortyGigE0/108         routed    down     down   QSFP+         off          N/A          N/A
  Ethernet112      89,90,91,92      40G   9100  fortyGigE0/112  PortChannel01      up       up   QSFP+         off   ARISTA01T1  Ethernet1/1
  Ethernet116      93,94,95,96      40G   9100  fortyGigE0/116  PortChannel02    down     down   QSFP+         off   ARISTA02T1  Ethernet1/1
  Ethernet120     97,98,99,100      40G   9100  fortyGigE0/120  PortChannel03    down     down   QSFP+         off   ARISTA03T1  Ethernet1/1
  Ethernet124  101,102,103,104      40G   9100  fortyGigE0/124  PortChannel04      up       up   QSFP+         off   ARISTA04T1  Ethernet1/1
PortChannel01              N/A      40G   9100             N/A         routed    down       up     N/A         N/A
PortChannel02              N/A      40G   9100             N/A         routed    down       up     N/A         N/A
PortChannel03              N/A      40G   9100             N/A         routed    down       up     N/A         N/A
PortChannel04              N/A      40G   9100             N/A         routed    down       up     N/A         N/A

[stcheng]

my concern is that if there's something cabling/configuration issue, the real fact does not align with the information in the configuration database. Then the output will be misleading.

[jleveque]

As comments, plus please replace instances of "neighbour" with the American English spelling, "neighbor".

[jleveque]

This output is not displaying properly in the rendered Markdown. Please fix.

[prsunny]

my concern is that if there's something cabling/configuration issue, the real fact does not align with the information in the configuration database. Then the output will be misleading.

Agree @stcheng . However I thought we can compare this output with 'show lldp neighbor' to see if there is a miswiring.

[stcheng]

@prsunny agree. i would recommend some components in LLDP docker could write the current neighbors into the database. that would be a useful piece of information.

[prsunny]

retest this please