Merge PR #2675 (Bugfix for GCHP to read meteorology from YAML)

This merge brings PR #2675 (Fixed the problem that GCHP cannot read
meteorology field from yaml, by @yantosca) into the GEOS-Chem
"no-diff-to-benchmark" development stream.

According to @lizziel:

  I believe this fixes an issue brought in with the updates for
  GEOS-IT in dev/no-diff-to-benchmark (see PR #2523). It would only
  show up for GEOS-FP and GEOS-IT runs which we do not test in
  integration/AWS testing, and is not in any previously released
  versions. It therefore does not need an update to the changelog.

Signed-off-by: Bob Yantosca <yantosca@seas.harvard.edu>

GeosCore/input_mod.F90

@@ -609,10 +609,28 @@ SUBROUTINE Config_Simulation( Config, Input_Opt, RC )
     ENDIF
     Input_Opt%CHEM_INPUTS_DIR = TRIM( v_str )
 
+#if defined( MODEL_GCHP )
     !------------------------------------------------------------------------
-    ! Set other fields of Input_Opt accordingly
+    ! Meteorology field
     !------------------------------------------------------------------------
+    key   = "simulation%met_field"
+    v_str = MISSING_STR
+    CALL QFYAML_Add_Get( Config, TRIM( key ), v_str, "", RC )
+    IF ( RC /= GC_SUCCESS ) THEN
+       errMsg = 'Error parsing ' // TRIM( key ) // '!'
+       CALL GC_Error( errMsg, RC, thisLoc )
+       RETURN
+    ENDIF
+    Input_Opt%MetField = TRIM( v_str )
+#endif
+
+#if defined( MODEL_GEOS )
     Input_Opt%MetField        = 'See ExtData.rc'
+#endif
+
+    !------------------------------------------------------------------------
+    ! Set other fields of Input_Opt accordingly
+    !------------------------------------------------------------------------
     Input_Opt%DATA_DIR        = 'N/A'
     Input_Opt%RUN_DIR         = 'N/A'