interp.c: remove two assertions that cannot be checked without the page table
interp.c: remove two assertions that cannot be checked without the page table

`!Is_in_value_area(pc)` is always false if we turn the page table off.
A better check would be `caml_find_code_fragment_by_pc(pc) != NULL`,
but I feel this is too costly even for the debug mode of the interpreter.

gerdstolpmann/ocaml,gerdstolpmann/ocaml,gerdstolpmann/ocaml,gerdstolpmann/ocaml,gerdstolpmann/ocaml