Add gpio default check to oeb check

[d-m-bailey]

Defaults for each gpio should be consistent with the analog, in, out, and oeb connections.

Add a check for inconsistencies based on https://docs.google.com/document/d/1bjmTO3ltCY-aRiNPkIlxbMTUPZ0887cxb2FdVshmwSM/edit