gta02-core: CPU broken down into smaller pieces

[Werner Almesberger]

Dave remarked that it may be difficult to fit things into A4 if we
have fairly large CPU blocks. So he broke the CPU down into smaller
components that can be combined as desired, a bit like LEGO bricks.

The units are as follows:

ABCDEFGHIJKLMNOP
||||||||||||||||
||||||lcd||||iic
|||||adc||||iis|
||||uart|||timer
|||eint|||usb ||
||spi  ||nand ||
|sdio  |sdram |power
mem    camera clock+control+jtag

I've updated the expanded schematics accordingly:
http://people.openmoko.org/werner/gta02-core/gta02-core-expanded-all.ps.gz

We also found that the inverted pins can get a bit tricky, e.g.,
when there's a pin that has multiple functions, some inverted,
others not, putting a circle for inversion would be misleading.

So the new convention is that only pins that are always inverted
get the circle, and the names of pin functions that are inverted
get an "n" prefix. We can then later automatically generate
overlines or such from the prefix. Example: nFWE/GPA19

- Werner