Refactor some max_patch_per_col and maxsoil_patches loops

[slevis-lmwg]

Description of changes

Issue #2025 shows examples of such loops that can be refactored for a clearer and more efficient code.

Specific notes

Contributors other than yourself, if any:
@glemieux @ekluzek @billsacks

CTSM Issues Fixed (include github issue #):
#2025

Are answers expected to change (and if so in what way)?
No, based on most recent testing.

Any User Interface Changes (namelist or namelist defaults changes)?
No.

Testing performed, if any:
...on the changes that I have made this far:
PASS ./create_test SMS_D_Ld3.f10_f10_mg37.I1850Clm50BgcCrop.cheyenne_intel.clm-default -c /glade/p/cgd/tss/ctsm_baselines/ctsm5.1.dev130
Cheyenne test-suite is in progress and hasn't raised any failures this far

[slevis-lmwg]

@rgknox I added you as reviewer, since you pointed out that you performed a similar (or the same) refactor in CNCIsoFluxMod yourself.

Test-suites:
Cheyenne OK
Izumi OK

[slevis-lmwg]

Test-suites:
Izumi ./run_sys_tests -s aux_clm -c ctsm5.1.dev131 -g ctsm5.1.dev134 PASS

Cheyenne WAIT for compute nodes to become available

[slevis-lmwg]

Since this PR is bfb, I agreed with @ekluzek that it could be merged with one of his other bfb PRs if he so decides.

[ekluzek]

I tried merging this with #1959 to see how ugly the merge would be. It's ugly enough that we should wait until after #1959 comes in.

The files with merge conflicts are:

both modified:   src/biogeochem/CNCIsoFluxMod.F90
both modified:   src/biogeochem/CNDriverMod.F90
both modified:   src/biogeochem/CNPhenologyMod.F90
both modified:   src/main/clm_initializeMod.F90
both modified:   src/soilbiogeochem/SoilBiogeochemVerticalProfileMod.F90

For the last two the merges are pretty trivial. The top three have merges that aren't completely horrible, but complex enough that we should wait. Then a few that are trivial. When this does come in it might be good for a few of us to examine them closely to make sure we are adopting the best solution. Probably at least @slevis-lmwg and @rgknox. And I'd be willing to part of that as well.

So I'm leaving this as a draft, to come in later.

[slevis-lmwg]

Resolved conflicts and this test passed:
SMS_D_Ld3.f10_f10_mg37.I1850Clm50BgcCrop.cheyenne_intel.clm-default
I will push to the PR and run test-suites next.

[slevis-lmwg]

Izumi test-suite PASS

[slevis-lmwg]

Updated to dev137 and running test-suites. I plan to merge this tomorrow.

@ekluzek would you like to review this PR before I merge? If so, either late this afternoon or tomorrow morning. Let me know what you think. Or would you prefer that I reach out to someone else?

[ekluzek]

I think it would be good for me to look it over. I'll try to get to that tonight. I'm not sure there's anyone else. @rgknox did work on this so maybe him. But, it's too late in the day to expect that.

[slevis-lmwg]

Test-suites
izumi PASS
cheyenne OK

[ekluzek]

Ahhh, yes this is a nice improvement, just loop over the soil patches in the filter, and remove the if statements to make sure they are active and within range.

[ekluzek]

OK, this is awesome, and results in a nice cleanup of the code. Not having to send both column and patch filters down is a nice simplification. And the result looks a lot cleaner (and slightly more efficient) than how this was previously done. Glad you worked on this and bringing it in.

I have one small request in the ChangeLog.

[ekluzek]

It's helpful to give the summary of the issue fixed in the ChangeLog, since the issue isn't connected to github.

[ekluzek]

I usually give the one line comment for PR's, but it's OK here. That's important when several PR's are merged together. But, with one PR in a tag, there's no reason to give the description. It's also easier for a single PR in a tag to just give the number, so I'll do that in the future as well.