Golang syscall: missing Errno on openbsd/386, openbsd/arm and openbsd/amd64

The syscall package is missing EBADMSG, ENOTRECOVERABLE, EOWNERDEAD and EPROTO on openbsd/386, openbsd/arm and openbsd/amd64. These are the earliest OpenBSD ports and they did not exist in the system headers when the relevant zerror_* file was generated. Given syscall is largely frozen, these have not been recently regenerated or updated.

Given that these already exist for all other ports, it makes sense to include them for consistency.

Issue noted by Kirill Korinsky.

Comment From: gopherbot

Change https://go.dev/cl/592795 mentions this issue: syscall: selectively update zerrors_* on openbsd/386, openbsd/arm and openbsd/amd64