[submodule] Update submodule sonic-linux-kernel to the latest HEAD au…

…tomatically (sonic-net#789)

#### Why I did it
src/sonic-linux-kernel
```
* 971a5d3 - (HEAD -> 202412, origin/HEAD, origin/202412) [code sync] Merge code from sonic-net/sonic-linux-kernel:202411 to 202412 (#28) (21 hours ago) [mssonicbld]
```
#### How I did it
#### How to verify it
#### Description for the changelog