OAC submodule pulled from my own fork

[abouteiller]

Thank you for taking the time to submit an issue!

Background information

What version of Open MPI are you using? (e.g., v3.0.5, v4.0.2, git branch name and hash, etc.)

main / ee324be

Describe how Open MPI was installed (e.g., from a source/distribution tarball, from a git clone, from an operating system distribution package, etc.)

Forked Open MPI, pulled from my own repo

Details of the problem

git submodule update --init --recursive fails because it tries to obtain the git repo abouteiller/oac, which does not exist (if it existed, it may not contain the wanted hash, as it may become outdated w.r.t. the origin/upstream).

Proposed resolution

Change ../oac to ../../open-mpi/oac in .gitmodules

[bwbarrett]

happy to take a pull request...