Bad handling of both C-style and C++ function pointers

[JakeHillion]

Function pointers are handled slightly strangely in the current implementation.

Issues:

• C-style function pointers don't report the function's address in the pointer field of the output.
• Some attempt to follow a C-style function pointer is made, returning a nonsensical result - we shouldn't try to follow function pointers.
• C++ style function pointers (std::function) don't report the function's address in the pointer field of the output.

### Affected tests

• OidIntegration.pointers_function_raw
• OidIntegration.pointers_function_raw_chase
• OidIntegration.pointers_function_raw_null
• OidIntegration.pointers_function_std_function
• OidIntegration.pointers_function_std_function_chase
• OidIntegration.pointers_function_std_function_null