C3/C4 assignment is incorrect in Ryan 1991 leaf maintenance respiration code

[JessicaNeedham]

EDPftvarcon_inst%c3psn(ft) is 0 for C4 and 1 for C3 plants:

fates/parameter_files/fates_params_default.cdl

Line 343 in 6d424f4

fates_leaf_c3psn:long_name = "Photosynthetic pathway (1=c3, 0=c4)" ;

But in the Ryan 1991 leaf MR code the wrong check is used meaning that the C4 temperature sensitivity adjustment is being used for C3 plants (and vice versa):

fates/biogeophys/FatesPlantRespPhotosynthMod.F90

Line 2120 in 6d424f4

if (nint(EDPftvarcon_inst%c3psn(ft)) /= 1) then

This code should instead use the c3c4_path_index used in other places in the code (e.g.):

fates/biogeophys/FatesPlantRespPhotosynthMod.F90

Line 1180 in 6d424f4

c3c4_path_index = nint(EDPftvarcon_inst%c3psn(ft))