Add config options to control init topo smoothing

Up to now, topography smoothing has been disabled in MPAS-Ocean
init mode.  This merge adds config options to control it
(the number of iterations and the weight of a cell vs. its
neighbors in each iteration).  By default, topography smoothing
is still off.

compass/ocean/tests/global_ocean/global_ocean.cfg

@@ -47,6 +47,11 @@ btr_dt_per_km = 1.5
 
 # Maximum allowed Haney number for configurations with ice-shelf cavities
 rx1_max = 20
+# the number of iterations of topography smoothing
+topo_smooth_iterations = 0
+# the weight given to the central cell during each iteration of smoothing,
+# where the n cellsOnCell (neighbors) are given a weight (1-weight)/n.
+topo_smooth_weight = 0.9
 
 # number of cores to use
 init_ntasks = 36

compass/ocean/tests/global_ocean/init/initial_state.py

@@ -139,9 +139,21 @@ def setup(self):
         Get resources at setup from config options
         """
         self._get_resources()
-        rx1_max = self.config.getfloat('global_ocean', 'rx1_max')
-        self.add_namelist_options({'config_rx1_max': f'{rx1_max}'},
-                                  mode='init')
+        section = self.config['global_ocean']
+        rx1_max = section.getfloat('rx1_max')
+        topo_smooth_iterations = section.getint('topo_smooth_iterations')
+        topo_smooth_weight = section.getfloat('topo_smooth_weight')
+
+        options = {
+            'config_rx1_max':
+                f'{rx1_max}',
+            'config_global_ocean_topography_smooth_iterations':
+                f'{topo_smooth_iterations}',
+            'config_global_ocean_topography_smooth_weight':
+                f'{topo_smooth_weight}',
+        }
+
+        self.add_namelist_options(options, mode='init')
 
     def constrain_resources(self, available_resources):
         """

compass/ocean/tests/global_ocean/init/namelist.init

@@ -53,4 +53,3 @@ config_global_ocean_depth_conversion_factor = 1.0
 config_global_ocean_minimum_depth = 10
 config_global_ocean_deepen_critical_passages = .false.
 config_block_decomp_file_prefix = 'graph.info.part.'
-config_global_ocean_topography_smooth_iterations = 0