BRCM SAI 5.0.0.8 Catch up fixes since 5.0.0.6

[gechiang]

Why I did it

Fix #8300

Catch up on fixes from BRCM SUG repo to pick up fixes after 5.0.0.6 all the way up to 5.0.0.8
Fixes include the following:

  CS00012201827: Warmreboot causes syncd crash with  SAI_API_UNSPECIFIED:syncdb_data_file_read:2230 Failed to parse JSON: error -2
  DNX: Fix for ACL table create with v6 next hdr attr
  and many unspecified changes that also went into 5.0.0.8

How to verify it

Preliminary tests looks fine on both XGS (gechiang) and DNX (judyjoseph)
On XGS testing done as following:
BGP neighbors were all up with proper routes programmed
interfaces are all up
Manually ran the following test cases on 7260CX3 T0 DUT and all passed:

     ipfwd/test_dir_bcast.py
     fdb/test_fdb.py
     fib/test_fib.py
     vlan/test_valn.py

Also validated for for CS00012201827 (#8300)

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

• 201811
• 201911
• 202006
• 202012
• 202106

Description for the changelog

BRCM SAI 5.0.0.8 Catch up fixes since 5.0.0.6

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

[gechiang]

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[gechiang]

/azp run

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