Fix MPI_WTIME interface warning in debug build using mpi_f08

[mingchen-NOAA]

Pull Request Summary

This PR resolves the Intel warning #8889: Explicit interface or EXTERNAL declaration is required for MPI_Wtime in wav_wrapper_mod.F90.

Description

The fix imports MPI_Wtime from the mpi_f08 module to provide a proper explicit interface and removes the incorrect local declarations that previously treated MPI_Wtime as a real variable. This aligns the code with modern MPI usage, improves type safety, and avoids compiler ambiguity.

This fix successfully resolves the Intel warnings in debug build:

wav_wrapper_mod.F90(53): warning #8889: Explicit interface or EXTERNAL declaration is required.   [MPI_WTIME]
wav_wrapper_mod.F90(76): warning #8889: Explicit interface or EXTERNAL declaration is required.   [MPI_WTIME]

No answers are expected to be changed.

Issue(s) addressed

addressing issue #1501

Commit Message

Check list

• Branch is up to date with the authoritative repository (NOAA-EMC) develop branch. up-to-date with dev/ufs-weather-model
• Checked the checklist for a developer submitting to develop.
• If a version number update is required, checked the updating version number checklist.
• If a new feature was added, a regression test for testing the new feature is added.

Testing

• How were these changes tested? UFS-WM RT Tests
• Are the changes covered by regression tests? (If not, why? Do new tests need to be added?)
• Have the matrix regression tests been run (if yes, please note HPC and compiler)?
• Please indicate the expected changes in the regression test output, (Note the list of known non-identical tests.)
• Please provide the summary output of matrix.comp (matrix.Diff.txt, matrixCompFull.txt and matrixCompSummary.txt):

RegressionTests_hercules.log