Avoid allocating unused arrays in diabatic_driver

- In order to call calculateBuoyancyFlux2d() along with the ePBL
  the KPP fields are all allocated but not all are needed. This
  allocates only those used.

src/parameterizations/vertical/MOM_diabatic_driver.F90

@@ -2073,13 +2073,15 @@ subroutine diabatic_driver_init(Time, G, GV, param_file, useALEalgorithm, diag,
   ! CS%useKPP is set to True if KPP-scheme is to be used, False otherwise.
   ! KPP_init() allocated CS%KPP_Csp and also sets CS%KPPisPassive
   CS%useKPP = KPP_init(param_file, G, diag, Time, CS%KPP_CSp, passive=CS%KPPisPassive)
-  if (CS%useKPP .or. CS%use_energetic_PBL) then
+  if (CS%useKPP) then
     allocate( CS%KPP_NLTheat(isd:ied,jsd:jed,nz+1) )   ; CS%KPP_NLTheat(:,:,:)   = 0.
     allocate( CS%KPP_NLTscalar(isd:ied,jsd:jed,nz+1) ) ; CS%KPP_NLTscalar(:,:,:) = 0.
+  endif
+  if (CS%useKPP .or. CS%use_energetic_PBL) then
     allocate( CS%KPP_buoy_flux(isd:ied,jsd:jed,nz+1) ) ; CS%KPP_buoy_flux(:,:,:) = 0.
     allocate( CS%KPP_temp_flux(isd:ied,jsd:jed) )      ; CS%KPP_temp_flux(:,:)   = 0.
     allocate( CS%KPP_salt_flux(isd:ied,jsd:jed) )      ; CS%KPP_salt_flux(:,:)   = 0.
- endif
+  endif
 
   call get_param(param_file, mod, "SALT_REJECT_BELOW_ML", CS%salt_reject_below_ML, &
                  "If true, place salt from brine rejection below the mixed layer,\n"// &
@@ -2319,11 +2321,13 @@ subroutine diabatic_driver_end(CS)
   call entrain_diffusive_end(CS%entrain_diffusive_CSp)
   call set_diffusivity_end(CS%set_diff_CSp)
   if (CS%useKPP .or. CS%use_energetic_PBL) then
-    deallocate( CS%KPP_NLTheat )
-    deallocate( CS%KPP_NLTscalar )
     deallocate( CS%KPP_buoy_flux )
     deallocate( CS%KPP_temp_flux )
     deallocate( CS%KPP_salt_flux )
+  endif
+  if (CS%useKPP) then
+    deallocate( CS%KPP_NLTheat )
+    deallocate( CS%KPP_NLTscalar )
     call KPP_end(CS%KPP_CSp)
   endif
   if (CS%useConvection) call diffConvection_end(CS%Conv_CSp)