[submodule] Update submodule sonic-linux-kernel to the latest HEAD automatically (sonic-net#833)

#### Why I did it
src/sonic-linux-kernel
```
* 6f7c5cf - (HEAD -> 202412, origin/HEAD, origin/202412) [code sync] Merge code from sonic-net/sonic-linux-kernel:202411 to 202412 (#32) (21 hours ago) [mssonicbld]
```
#### How I did it
#### How to verify it
#### Description for the changelog

Author: mssonicbld