rtc-opal: Fix handling of firmware error codes, prevent busy loops

[Michael Ellerman]

Alexandre Belloni <alexandre.belloni at bootlin.com> writes:

> On 06/02/2018 at 16:22:47 +1100, Michael Ellerman wrote:
>> > Just a note to let you know that this patch should have gone through my
>> > tree but it was not sent to linux-rtc or me.
>> 
>> Sorry, I saw it had been languishing for a long time and assumed you'd
>> missed it.
>> 
>> Happy to revert/rework it if you're not happy with it.
>> 
>
> No, that's fine. It's just that the commit title stands out when using
> git log --oneline and that triggered my OCD ;)

Oh no! Now I'm *really* sorry, that's the worst! :)

cheers