[gta02-core] ECN0010 re-opened (was Re: More audio considerations)

[Werner Almesberger]

I wrote:
> Comments, particularly about the latter issue ?

No comments, so I moved it to "Execute".

Also, let's try to use IO_3V3 then. As a precaution, I'd add a 0R
before LDO34IN, so that it can be reworked to use Vsys in case
there are problems.

We should also rename CODEC_3V3 to either CODEC_3V or - probably
better - just CODEC_VDD.

- Werner