[Mellanox] Support DSCP remapping in Dual-ToR topo for SN4700-O8V48, update buffers for t0

[ayurkiv-nvda]

Why I did it

Need to provide support for SN4700-O8V48 for Dual-ToR.
DSCP remapping is a part of Dual-ToR feature, so need to update HWSKU files to align with requirements

Work item tracking

• Microsoft ADO (number only):

How I did it

• Use QoS config the same as used in 4600C platform that is already supports Dual-ToR
• update buffers for T0

How to verify it

Run DSCP remapping test for Dual-ToR

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

Link to config_db schema for YANG module changes

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

[stephenxs]

I'm sorry but I forgot there was some compromise in calculating 400G headroom for 4700.
So, let's take the headroom sizes for both 100G and from pg_profile_lookup.ini to calculate the buffer pool size.
t0:
400G uplink: 400000 40m 38912 38912 144384, => headroom size in the excel: 179, operate headroom size: 38
200G downlink: 200000 5m 19456 19456 66560, => headroom size in the excel: 84, operate headroom size: 19

[ayurkiv-nvda]

I'm sorry but I forgot there was some compromise in calculating 400G headroom for 4700. So, let's take the headroom sizes for both 100G and from pg_profile_lookup.ini to calculate the buffer pool size. t0: 400G uplink: 400000 40m 38912 38912 144384, => headroom size in the excel: 179, operate headroom size: 38 200G downlink: 200000 5m 19456 19456 66560, => headroom size in the excel: 84, operate headroom size: 19

Recalculated.
New data for buffers:

ingress pool : 47040 x 1024
lossless pool xoff: 5096 x 1024
egress pool: 47040 x 1024