Add PocketBeagle 2 documentation updates

See merge request docs/docs.beagleboard.io!188

Fix build errors and BeagleY-AI demos index

Closes #85

See merge request docs/docs.beagleboard.io!187

fix#84feedback-missing-pointers

See merge request docs/docs.beagleboard.io!184

PicoRV-Softcore documentation

See merge request !179

See merge request docs/docs.beagleboard.io!175

See !175
for some of my motivation on these fixes

Fix librobotcontrol

See merge request docs/docs.beagleboard.io!177