correctly no matter how the "gpio_defaults_block.mag" and
"gl/gpio_defaults_block.v" are defined. Previously it assumed
that they both defined all bits as zero, which was not the case
for the layout. Now both define bit value 0x0402 and the script
can flip bits either direction as needed in both verilog and
layout
blocks; that is, there are special versions of the block for the
first 6 GPIO pins. That should allow the GL netlists to simulate,
although the end goal is to have the gen_gpio_defaults.py script
modify the GL netlists to exactly match the configuration, as is
done for the .mag layouts.