[Icc-avr] io header files update

[Johannes Assenbaum]

>> How do you think of iccioavr.h? Please choose one of the following:
>>
>>    I use it.
>>    I heard people talking about.
>> X  Ahm, what?

> Very good idea, though, and I'll use it in new scratch projects.

> However, I often start with the skeleton from the App Builder and that
> still emits the device-specific header name.

It's just one line to change in App Builder output. For me it's not so much compared to changes I normally do on io init, to invoke my project's pin/bit names...

However, it'd really be nice, not to need to do that extra change. So, Richard, would you please tell App Builder writer to use iccioavr.h in future?

Best regards,
Johannes