Fix #1107, Remove unreachable branch (superfluous if condition)

[thnkslprpt]

Checklist

• I reviewed the Contributing Guide.
• I signed and emailed the appropriate Contributor License Agreement to GSFC-SoftwareRelease@mail.nasa.gov and copied cfs-program@lists.nasa.gov.

Describe the contribution

• Fixes Unreachable branch on unknown fstype in OS_FileSys_Initialize #1107
  • Superfluous if condition removed - removing an unreachable branch (condition is always true) and slightly improving test coverage.

Testing performed
GitHub CI actions (incl. Build + Run, Unit Tests etc.) all passing successfully.

Expected behavior changes
No change to behavior.

Contributor Info
Avi Weiss @thnkslprpt

[skliper]

Does this change branch coverage results at all? If so I recommend updating:

osal/.github/workflows/standalone-build.yml

Line 13 in b5dd01c

allowed_ncov_branches: 4

[thnkslprpt]

Does this change branch coverage results at all? If so I recommend updating:

osal/.github/workflows/standalone-build.yml

Line 13 in b5dd01c

allowed_ncov_branches: 4

Thanks!

I need a checklist or something - that's the second time I forgot to update these parameters for allowed exceptions to coverage.

Anyway I updated it now - it had actually become out-of-date at some point before this PR (was allowing 4 exceptions when the main branch was already down to only 3 missed branches).

I've lowered it now from 4 to 2.

[jphickey]

If I remember correctly, this could be a remnant from the days when there was a global volume table in OSAL that could pre-init these items. I think we've fully purged that, and I concur I can't see any path though the code where this condition could ever be false.