Backport changes from #11018
Signed-off-by: Neetha John <nejo@microsoft.com>
Why I did it
As part of PCBB changes, we need to enable 2 extra lossless queues. The changes in this PR are done to adjust only the reserved sizes on Th2 for the additional 2 lossless queues
Calculations are done based on 40 downlinks for T1 and 16 uplinks for dual ToR
How to verify it
Verified that the rendering works fine on Th2 dut
Unit tests have been updated to reflect the modified buffer sizes when pcbb is enabled. There are existing testcases that will test the original buffer sizes when pcbb is disabled. With these changes, was able to build sonic-config-engine wheel successfully
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