Add Variability to Carbon Long Names

[acollow]

At the present time all carbon fields have long names that state "CA.*, which is not ideal. The SI has implemented a solution with the ACG based on the following block of code in the carbon grid comp:
if (comp_name(1:5) == 'CA.oc') then
GCsuffix = 'OC'
else if (comp_name(1:5) == 'CA.bc') then
GCsuffix = 'BC'
else if (comp_name(1:5) == 'CA.br') then
GCsuffix = 'BR'
end if

In order to implement the GCsuffix getting used by the ACG, a change is needed for CA2G_GridComp/CMakeLists.txt.