The symbol handling has been extended to register whether a symbol
represents a function or not. This information is then used to register,
during the global data harvesting phase, all the function symbols and
explicitly mark them through the "FunctionSymbol" `JTReason`.

We use this information during the CFEP harvesting phase to integrate
the information produced by the function boundaries detection with
potential unidentified CFEPs.

This option can be enabled with the `--use-debug-symbols`, which
supersedes `--use-sections`.