#2403: compile failure with gfortran 10 when using CCTK_PointerTo

Comment (by Roland Haas):

Hmm, I may be missing an indirection step: https://software.intel.com/en-us/forums/intel-fortran-compiler/topic/270769 looks like passing a c_ptr to a C function passes a pointer to a pointer and I need to add a “value” somewhere in its interface declaration.