FATES doesn't work with new biomass heat storage option added into clm5_1 physics needs stem/leaf biomass (and move biomass calc to veg model)

FATES doesn't work with the new biomass heat storage (BHS) option which is turned on for clm5_1 physics. The missing bit is that FATES needs to tell CTSM as HLM what the stem and leaf biomass is. It already tells it LAI and SAI and HTOP which are also needed. BHS was added in with ctsm5.1.dev021.

NOTE: BHS is only turned on for trees and shrubs.

The calculation of biomass heat storage is in CanopyFluxes. Inputs to the calculation are:

esai, elai, htop. -- These are already provided
--- These will need to be set for FATES
stem_biomass
leaf_biomass

parameters on the parameter file are: fbw (fraction of biomass that's water), wood_density
for the SP version: dbh_param (diameter at breast height)

For the big-leaf version nstem (stem number density) is on the parameter file as well. Does FATES calculate this?

Here's a section that will likely need a FATES option that currently only has a BGC option or SP option. It's possible that FATES could use the BGC option if it sets stem_biomass and it's ok to use nstem from the parameter file.

``` fortran
! if using Satellite Phenology mode, use values in parameter file
! otherwise calculate dbh from stem biomass
if(use_cn) then
if(stem_biomass(p) > 0._r8) then
dbh(p) = 2._r8 * sqrt(stem_biomass(p) * (1._r8 - fbw(patch%itype(p))) &
/ ( shr_const_pi * htop(p) * k_cyl_vol &
* nstem(patch%itype(p)) * wood_density(patch%itype(p))))
else
dbh(p) = 0._r8
endif
else
dbh(p) = dbh_param(patch%itype(p))
endif
```

Also as noted below we should move the biomass calculations to inside of their source veg model (BGC code, SP code, or FATES code).