doc: show where self-test results can be found

[paumr]

As a first-time user I was wondering on where to find the device-self-test results.

I think adding this information to the device-self-test documentation would be quite useful.

[igaw]

Looks good.

Just a nit: Could you add your Signed-off-by to the commit message? Or I can add it if it's okay for you.

Thanks!

[paumr]

Thanks! Sure, I signed the commit - thanks for the review.

[igaw]

We follow the Linux kernel mailing list workflow, thus commit message itself should be something like

doc: show where self-test results can be found

Point out where find results when running the self tests.

Signed-off-by: My Name/alias <email.address.foo>