Juan 18/11/2021:mode_mg_read_param.f90, Pb detected with crayftn compiler => format(L6) -> (I6)

(cherry picked from commit fbb500d79524ea4e9725680b562f2231beefce6b)

src/ZSOLVER/tensorproductmultigrid_Source/mode_mg_read_param.f90

@@ -448,7 +448,7 @@ subroutine read_multigrid_parameters(filename,mg_param)
     write(STDOUT,NML=parameters_multigrid)
     write(STDOUT,'("---------------------------------------------- ")')
     write(STDOUT,'("Multigrid parameters")')
-    write(STDOUT,'("    verbose      = ",L6)') verbose
+    write(STDOUT,'("    verbose      = ",I6)') verbose
     write(STDOUT,'("    levels       = ",I3)') n_lev
     write(STDOUT,'("    splitlevel   = ",I3)') lev_split
     !