ENH: GeometricBoundaryField: short-circuit patch rgoups test

src/OpenFOAM/fields/GeometricFields/GeometricField/GeometricBoundaryField.C

@@ -50,6 +50,8 @@ readField
     }
 
 
+    label nUnset = this->size();
+
     // 1. Handle explicit patch names. Note that there can be only one explicit
     //    patch name since is key of dictionary.
     forAllConstIter(dictionary, dict, iter)
@@ -70,10 +72,16 @@ readField
                         iter().dict()
                     )
                 );
+                nUnset--;
             }
         }
     }
 
+    if (nUnset == 0)
+    {
+        return;
+    }
+
 
     // 2. Patch-groups. (using non-wild card entries of dictionaries)
     // (patchnames already matched above)