Variables missing from FatesColdAllVars testmod

### Brief summary of bug

The `FatesColdAllVars` testmod is supposed to save every single FATES variable. However, there are [285 missing as of ctsm5.3.009](https://gist.github.com/samsrabin/1f74ab4e79fa849efbc3ab09c69a8220).

### General bug information

**CTSM version you are using:** ctsm5.3.009

**Does this bug cause significantly incorrect results in the model's science?** No

**Configurations affected:** Any test with the `FatesColdAllVars` testmod.

### Details of bug

Might be resolved by #2061.

### Important output or errors that show the problem

Can be tested from the top of a CTSM checkout like so (bash):
```bash
fates_hist_int_mod=src/fates/main/FatesHistoryInterfaceMod.F90
fatescoldallvars_nl=cime_config/testdefs/testmods_dirs/clm/FatesColdAllVars/user_nl_clm
for v in $(grep -oE "vname\s*=\s*[\"']\w+[\"']" $fates_hist_int_mod | sed -E "s/vname\s*=\s*//g" | sed "s/'//g"); do
nfound=$(grep "'$v'" $fatescoldallvars_nl | wc -l)
if [[ $nfound -gt 1 ]]; then
echo "$v: multiple matches"
elif [[ $nfound -eq 0 ]]; then
echo $v
fi
done | sort
```