Hardening improvements

[xobs]

This patchset includes some improvements I made while preparing this to be incorporated into a Skywater shuttle run:

• BSD license attached to all source files
• Return a version number when reading from the NONE register
• Initialize values on device reset
• Support coalescing multiple PIO outputs

It has not yet been proven in silicon, but it has been run through a testbench and I will be attempting to submit it as part of MPW-8.