[type reconstruction] type reconstructions for function pointers aren't recompilable

[pdreiter]

Seeing weirdness with reconstructed typedefs related to function pointers.
e.g.

mjs_recomp.c:220:36: error: ‘ffi_fn_t’ redeclared as different kind of symbol
 typedef void (*mjs_func_ptr_t)void ffi_fn_t;
                                    ^~~~~~~~

Some investigation needed to determine the correct construction of this typedef.

Can duplicate this in the same manner as issue #6.