update Fortran codegen_simplified to support run-time ABC and reallocation
in matlab, if the index larger than the dimension size of the array in
an array set stmt, the array will grow to a larger one. and correspondingly,
we should reallocate memroy for that array in Fortran.
TODO there are several cases, the matlab interpreter cannot decide how to
grow the array, in these cases, error exception should be thrown out.
e.g:
a = ones(3,3);
a(3,4) = 0; % this is fine.
a(20) = 12; % this is an error.