IMPORTANT: Update arguments to intrisic functio PACK

[arango]

• Several versions of gfortran failed when the Fortran intrinsic function PACK had a pointer as the first argument. The PACK function is used when reading NetCDF files, and the CHECKSUM option is activated. So, for example, in nf_fread2d.F, we need to have instead:

        IF (Lchecksum) THEN
  # ifdef DISTRIBUTE
          Npts=(Imax-Imin+1)*(Jmax-Jmin+1)
          IF (.not.allocated(Cwrk)) allocate ( Cwrk(Npts) )
          Cwrk = PACK(Adat(Imin:Imax, Jmin:Jmax), .TRUE.)
          CALL get_hash (Cwrk, Npts, checksum, .TRUE.)
  # else
          Npts=(Ie-Is+1)*(Je-Js+1)
          IF (.not.allocated(Cwrk)) allocate ( Cwrk(Npts) )
          Cwrk = PACK(Adat(Is:Ie, Js:Je), .TRUE.)
          CALL get_hash (Cwrk, Npts, checksum)
  # endif
          IF (allocated(Cwrk)) deallocate (Cwrk)
        END IF
  
  

• Updated the gfortarn make configuration script to comment the -fsanitize compiling flags:

  #          FFLAGS += -fsanitize=address -fsanitize=undefined
  

  The sanitization in a newer version for gfortran requires a couple of libraries during compilation and execution.