fill %litr_lig_c_to_n_col for fates at same point as non-fates

Here is where we update soilbiogeochem_carbonflux%litr_lig_c_to_n_col(c):

https://github.com/ESCOMP/CTSM/blob/ctsm5.1.dev130/src/soilbiogeochem/SoilBiogeochemCarbonFluxType.F90#L1010

You can see that we do not perform an update to that array if fates is on, at least not at this location. If fates is on, we have a call to update the array at a different point in the call sequence, but presumably a compatible point. See here:

https://github.com/ESCOMP/CTSM/blob/3a8fb5c42d1139f71770b9107d181e51e5dbf824/src/utils/clmfates_interfaceMod.F90#L1330

@ekluzek and I agree that it would be more readable (and probably future-proofing if someone were to make changes here) if there was a call to some wrapper code clmfates_interfaceMod that handles filling this variable, from the same location as the non-fates filling.

For a fates run, we do