Resume issue after a longer sleep

[Werner Almesberger]

Andy Green wrote:
> I push a battery on
> there to get around some U-Boot issue where at one point early in boot
> it seems to require a battery around.

This might actually be hardware, namely be the PMU resetting
MBCC1.chgena to "off" in NoPower.

u-boot just prolongs the agony by not enabling it. In fact, I have
some doubts whether our logic to set chgena only when USB power is
available really makes sense on GTA02. There are a few things I
want to try this week.

- Werner