fix: Access colvarproxy_lammps object from correct rank

Author: giacomofiorin

lammps/src/COLVARS/fix_colvars.cpp

@@ -846,6 +846,10 @@ void FixColvars::end_of_step()
         }
       }
 
+      if (proxy->total_forces_enabled()) {
+        proxy->set_total_forces_valid();
+      }
+
     } else { // me != 0
       /* copy total force data into communication buffer */
       nme = 0;
@@ -864,10 +868,6 @@ void FixColvars::end_of_step()
       MPI_Rsend(comm_buf, nme*size_one, MPI_BYTE, 0, 0, world);
     }
 
-    if (proxy->total_forces_enabled()) {
-      proxy->set_total_forces_valid();
-    }
-
   }
 }