C1: fix "assert(has_printable_bci()) failed: _printable_bci should have been set" when using -XX:+PrintCanonicalization

[Roland Westrelin]

> But Local and Phi instructions are exceptions. They're never "linked" into
> the instruction list (they're just filled into a ValueStack), but they
> deserve something better than -99. They're more likely to cause trouble in
> Canonicalizer::set_canonical(x) by this call:
>
> x->input_values_do(&do_print_value);
>
> Which is why I did the change in the constructors of Local and Phi.

That makes sense.

Roland.