[Arista-7060X6-64PE-B, Arista-7060X6-16PE-384C-B]: Initialize SmartSAF (#24044)

Note: this is a manual backport to 202505 for sonic-net/sonic-buildimage#23908

#### Why I did it
To enable the SmartSAF feature on the targer platforms.

##### Work item tracking
- Microsoft ADO **(number only)**:

#### How I did it
Added SmartSAF settings to the Broadcom config/SAI profile files.

#### How to verify it
From the DUT's CLI, enter the Broadcom shell: `bcmsh`
Run `ps` and confirm that the cut thru mode for the desired interfaces is `Smart`.
Can also confirm `SMART_STORE_AND_FORWARD=1` by running: `bsh -c "lt traverse -l TM_SMART_STORE_AND_FORWARD_CONFIG"`

#### Which release branch to backport (provide reason below if selected)
- [ ] 202205
- [ ] 202211
- [ ] 202305
- [ ] 202311
- [ ] 202405
- [x] 202505

#### Tested branch (Please provide the tested image version)
202412, 202505

#### Description for the changelog
Update the BCM config files for Arista-7060X6-64PE-B, Arista-7060X6-16PE-384C-B to initialize SmartSAF functionality.

Author: mssonicbld