Remove check for zonal mean output with non-FV dycores.

### Issue Type

Code Clean-up

### Issue Description

Requesting zonal mean output when running with a non-FV dycore via setting the namelist varibles to turn on the `phys_grid_ctem` module results in output similar to the following in the atm log file:
```
FLDLST: Uzm in fincl(1, 3) only available with FV dycore
FLDLST: Vzm in fincl(2, 3) only available with FV dycore
FLDLST: Wzm in fincl(3, 3) only available with FV dycore
FLDLST: THzm in fincl(4, 3) only available with FV dycore
FLDLST: VTHzm in fincl(5, 3) only available with FV dycore
FLDLST: WTHzm in fincl(6, 3) only available with FV dycore
FLDLST: UVzm in fincl(7, 3) only available with FV dycore
FLDLST: UWzm in fincl(8, 3) only available with FV dycore
```
This incorrect output is from a code workaround implemented in `subroutine fldlst` (in cam_history.F90) before the `phys_grid_ctem` module was available. The purpose of the workaround was to allow running WACCM compsets with the SE dycore without having to modify the use case files which requested the zonal mean output.

The fix is not as simple as just removing the code workaround in `subroutine fldlst`. The request for zonal mean output in WACCM and some other chemisty use case files needs to be updated to include setting the namelist variables for the `phys_grid_ctem` module. This is addressed in issue #774, so the current issue depends on that one.

### Will this change answers?

No

### Will you be implementing this yourself?

Any CAM SE can do this