…t back to back Paladin ports up with Arista-7060X6-16PE-384C-O128S2

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#### Why I did it

Currently when we loaded HWSKU `Arista-7060X6-16PE-384C-O128S2` on two moby devices and connect their Paladin ports back to back, we can't get link up. It may help if we can get these links up and run the tests.

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

#### How I did it

Created a new `FANOUT` HWSKU containing special lanemap and polarity configs so that we can load `Arista-7060X6-16PE-384C-O128S2` on one Moby and `Arista-7060X6-16PE-384C-O128S2-FANOUT` and get Paladin ports up when connecting them back to back with the following setup:
```
Moby1                                    Moby2
HWSKU: Arista-7060X6-16PE-384C-O128S2    HWSKU: Arista-7060X6-16PE-384C-O128S2-FANOUT
Azure#17                 <->                  Azure#18
Azure#19                 <->                  Azure#20
Azure#21                 <->                  Azure#22
Azure#23                 <->                  Azure#24

Azure#18                 <->                  Azure#17
Azure#20                 <->                  Azure#19
Azure#22                 <->                  Azure#21
Azure#24                 <->                  Azure#23
```

#### How to verify it
Verified that all the Paladin ports can link up with the above setup.

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- [x] msft-202412

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#### Description for the changelog
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Created `Arista-7060X6-16PE-384C-O128S2-FANOUT` based on `Arista-7060X6-16PE-384C-O128S2` and only update lanemap and polarity settings in bcm config.

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