sonic-yang-models: WRED statistics yang

[rpmarvell]

Why I did it

Supporting WRED and ECN statistics in SONiC

Work item tracking

• Microsoft ADO (number only):

How I did it

Added new flex counter groups in yang file

How to verify it

Compiled the sonic.bin and loaded the image to DUT with all the WRED feature changes.

Which release branch to backport (provide reason below if selected)

• 201811
• 201911
• 202006
• 202012
• 202106
• 202111
• 202205
• 202211

Tested branch (Please provide the tested image version)

Description for the changelog

• Yang changes for WRED_ECN_QUEUE and WRED_ECN_PORT flex counter groups

Link to config_db schema for YANG module changes

https://github.com/sonic-net/sonic-buildimage/blob/master/src/sonic-yang-models/doc/Configuration.md#flex_counter_table

Dependent Pull Requests:
Sonic-utilities pull request : sonic-net/sonic-utilities#2807
Sonic-sairedis pull request : sonic-net/sonic-sairedis#1234
Sonic-swss : pull request : sonic-net/sonic-swss#2750
Sonic-swss common pull request : sonic-net/sonic-swss-common#777

A picture of a cute animal (not mandatory but encouraged)

[stephenxs]

https://github.com/sonic-net/sonic-buildimage/blob/master/dockers/docker-orchagent/enable_counters.py#L41 should also be updated to support WRED counters.
This is to disable counter-polling for the fast reboot to accelerate the converging process.
The logic is

1. counter polling is disabled by fast reboot script by writing the field into config_db.json directly
2. once the system reboots from the fast reboot, enable_counters will be invoked to re-enable the counter-polling.

Without update the logic, the WRED counters will be disabled after fast reboot.

[rpmarvell]

@stephenxs

https://github.com/sonic-net/sonic-buildimage/blob/master/dockers/docker-orchagent/enable_counters.py#L41 should also be updated to support WRED counters. This is to disable counter-polling for the fast reboot to accelerate the converging process. The logic is

1. counter polling is disabled by fast reboot script by writing the field into config_db.json directly
2. once the system reboots from the fast reboot, enable_counters will be invoked to re-enable the counter-polling.

Without update the logic, the WRED counters will be disabled after fast reboot.

====
WRED stats is not a default statistics. As far as i have verified using fast-reboot command, It retains the counterpoll status even after the fast-reboot is completed. It should be fine

[zhangyanzhao]

@lguohan @yxieca @kperumalbfn @donNewtonAlpha , @baxia-lan @Praveen-Brcm can anyone of you help to merge this PR? Thanks.