pledge breaks on OpenBSD 7.5 and current

[toddfries]

ossec/ossec_openbsd.go was added on Feb 22, 2022 via commit 67aad53
It works through OpenBSD 7.4
On OpeBSD 7.5 amd64 ...go version go1.22.1 openbsd/amd64 .. as of d2d286f
this breaks as below:

$ git pull
$ go generate ./...
$ GO111MODULE=on go install -v . ./...
$ ./go/bin/btcd --testnet
pledge failed: function not implemented

Same result with OpenBSD 7.5 amd64 -current with go1.22.3