Reduce GOTO statements from HAFS Fortran source codes

[BinLiu-NOAA]

Description

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From NCO SPA:
Please consider to remove or reduce GOTO statements, replace them with more
structured constants (if blocks, do loops, case blocks) in next HAFS upgrade.

under /lfs/h1/ops/para/packages/hafs.v1.0.3/

>for file in `find sorc -name "*.[fF]*" -type f` ; do egrep -iH "go[ ]*to" $file | grep -iv :c | grep -iv :\! ; done | wc -l
2938

Here are detailed GOTO statements in HWRF/HMON and HAFS -
hafs.v1.0.0 - goto - total 2938
hafs_forecast.fd 1954
hafs_gsi.fd 73
hafs_hycom_utils.fd 419
hafs_post.fd 0
hafs_tools.fd 257
hafs_tracker.fd 43
hafs_utils.fd 192

Proposed solution

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Related to (optional)

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• fixed by hafs-community/hafs/pull/<pr_number>
• dependent upon ufs-community/ufs-weather-model/pull/<pr_number>
• associated with noaa-emc/upp/pull/<pr_number>
• related to hafs-community/GSI/issues/<issue_number>

[BinLiu-NOAA]

Based on the counting @BijuThomas-NOAA did for the latest HAFSv2 package, here are the numbers of "goto"s from the production/hafs.v2 branch:

hafs.v2.0.0 - goto - total 2153
hafs_forecast.fd 1127
hafs_gsi.fd 72
hafs_hycom_utils.fd 440
hafs_post.fd 0
hafs_tools.fd 257
hafs_tracker.fd 43
hafs_utils.fd 214