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

…tomatically (sonic-net#17056)

#### Why I did it
src/sonic-linux-kernel
```
* a75a3df - (HEAD -> master, origin/master, origin/HEAD) arm64: Kconfig inclusions to fix PCI hang and MTD detection (sonic-net#350) (3 hours ago) [Pavan Naregundi]
```
#### How I did it
#### How to verify it
#### Description for the changelog