Remove unused pver argument in press_lim_idx (match ESCOMP/CAM) (ESCOMP#399)

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Originator(s): @jimmielin

Description (include the issue title, and the keyword ['closes',
'fixes', 'resolves'] followed by the issue number):
- remove unused `pver` argument in `press_lim_idx` to match the function
interface in ESCOMP/CAM
(https://github.com/ESCOMP/CAM/blob/cam_development/src/physics/cam/ref_pres.F90#L176)

Describe any changes made to build system: N/A

Describe any changes made to the namelist: N/A

List any changes to the defaults for the input datasets (e.g. boundary
datasets): N/A

List all files eliminated and why: N/A

List all files added and what they do: N/A

List all existing files that have been modified, and describe the
changes:
(Helpful git command: `git diff --name-status
development...<your_branch_name>`)
```
M       src/data/ref_pres.F90
   - remove unused `pver` argument in `press_lim_idx` to match the function interface in ESCOMP/CAM
```

If there are new failures (compared to the
`test/existing-test-failures.txt` file),
have them OK'd by the gatekeeper, note them here, and add them to the
file.
If there are baseline differences, include the test and the reason for
the
diff. What is the nature of the change? Roundoff?

derecho/intel/aux_sima:

derecho/gnu/aux_sima:

If this changes climate describe any run(s) done to evaluate the new
climate in enough detail that it(they) could be reproduced:

CAM-SIMA date used for the baseline comparison tests if different than
latest:

Author: jimmielin

src/data/ref_pres.F90

@@ -151,17 +151,17 @@ subroutine ref_pres_init(pref_edge_in, pref_mid_in, num_pr_lev_in)
       pref_mid_norm = pref_mid/psurf_ref
 
       ! Find level corresponding to the top of troposphere clouds.
-      trop_cloud_top_lev = press_lim_idx(pver, trop_cloud_top_press, &
+      trop_cloud_top_lev = press_lim_idx(trop_cloud_top_press, &
          top=.true.)
 
       ! Find level corresponding to the top for MAM processes.
-      clim_modal_aero_top_lev = press_lim_idx(pver, clim_modal_aero_top_press, &
+      clim_modal_aero_top_lev = press_lim_idx(clim_modal_aero_top_press, &
          top=.true.)
 
       ! Find level corresponding to the molecular diffusion bottom.
       do_molec_diff = (ptop_ref < do_molec_press)
       if (do_molec_diff) then
-         nbot_molec = press_lim_idx(pver, molec_diff_bot_press, &
+         nbot_molec = press_lim_idx(molec_diff_bot_press, &
             top=.false.)
       end if
 
@@ -194,12 +194,11 @@ end subroutine ref_pres_init
 !====================================================================================
 
    ! Convert pressure limiters to the appropriate level.
-   pure function press_lim_idx(pver, pres, top) result(lev_idx_lim)
+   pure function press_lim_idx(pres, top) result(lev_idx_lim)
 
       use vert_coord, only: index_top_layer, index_bottom_layer
 
       ! Input arguments:
-      integer, intent(in)         :: pver ! Number of vertical levels
       real(kind_phys), intent(in) :: pres ! Air pressure (Pa)
       logical,  intent(in)        :: top  ! Is this a top or bottom limit?