Enable fates sites to be initialized, but inactive, on virtual (i.e. zero-weight) columns

[glemieux]

If I understand correctly, it is possible for a column's %active status to be dynamically updated during runtime. We currently only initialize fates to run on columns that are active during elm initialization here:

E3SM/components/elm/src/main/elmfates_interfaceMod.F90

Lines 685 to 689 in 67abd00

	if ( (lun_pp%itype(l) == istsoil) .and. (col_pp%active(c)) ) then
	s = s + 1
	collist(s) = c
	this%f2hmap(nc)%hsites(c) = s
	col_pp%is_fates(c) = .true.

In attempting to enable the creation of "virtual" columns that capture a time-since-fire disturbance age value, we will need to make sure that we have fates sites setup on these virtual columns, but inactive. Note that we currently check to make sure that every clump has a fates site and will end the run if it does not here:

E3SM/components/elm/src/main/elmfates_interfaceMod.F90

Lines 800 to 804 in 67abd00

	if( this%fates(nc)%nsites == 0 ) then
	write(iulog,*) 'Clump ',nc,' had no valid FATES sites'
	write(iulog,*) 'This will likely cause problems until code is improved'
	call endrun(msg=errMsg(sourcefile, __LINE__))
	end if