Make EOSPAC build options dependent on EOSPAC

[jhp-lanl]

The SINGULARITY_EOSPAC_USE_MODERN_ERROR_CODES and SINGULARITY_EOSPAC_ENABLE_SHMEM options were not dependent on EOSPAC being ON. This PR makes them dependent on SINGULARITY_USE_EOSPAC.

PR Summary

PR Checklist

• N/A Adds a test for any bugs fixed. Adds tests for new features.
• N/A Format your changes by using the make format command after configuring with cmake.
• N/A Document any new features, update documentation for changes made.
• Make sure the copyright notice on any files you modified is up to date.
• After creating a pull request, note it in the CHANGELOG.md file.
• LANL employees: make sure tests pass both on the github CI and on the Darwin CI

If preparing for a new release, in addition please check the following:

• Update the version in cmake.
• Move the changes in the CHANGELOG.md file under a new header for the new release, and reset the categories.
• Ensure that any when='@main' dependencies are updated to the release version in the package.py

[jhp-lanl]

The SINGULARITY_EOSPAC_USE_MODERN_ERROR_CODES option was introduced in #507 and I didn't catch that it should be a dependent option.

[jhp-lanl]

Whoops... I used the wrong style for the change log. I'll correct it in another MR