Merge pull request #645 from ACCESS-NRI/unused_Faxa_

Remove unused Faxa_ vars

### Description of changes

Removes some unused fields from the CESM fields exchange module

### Specific notes

CMEPS Issues Fixed (include github issue #): closes #644

Are changes expected to change answers? (specify if bfb, different at roundoff, more substantial) 
bfb

Any User Interface Changes (namelist or namelist defaults changes)? None

### Testing performed

Adhoc tests show no impact from this change, results are bfb with previous results.

Author: billsacks

mediator/esmFldsExchange_cesm_mod.F90

@@ -1814,7 +1814,6 @@ subroutine esmFldsExchange_cesm(gcomp, phase, rc)
     ! to ocn: merged sensible heat flux
     ! ---------------------------------------------------------------------
     if (phase == 'advertise') then
-       call addfld_from(compatm , 'Faxa_sen')
        call addfld_aoflux('Faox_sen')
        call addfld_from(compice , 'Fioi_melth')
        call addfld_to(compocn , 'Foxx_sen')
@@ -1830,7 +1829,6 @@ subroutine esmFldsExchange_cesm(gcomp, phase, rc)
     ! to ocn: surface latent heat flux and evaporation water flux
     ! ---------------------------------------------------------------------
     if (phase == 'advertise') then
-       call addfld_from(compatm, 'Faxa_lat' )
        call addfld_aoflux( 'Faox_lat' )
        call addfld_aoflux( 'Faox_evap')
        call addfld_to(compocn, 'Foxx_lat' )