RFR: 8367862: debug.cpp: Do not print help message for methods ifdef'd out [v2]

[Kevin Walls]

On Fri, 19 Sep 2025 10:37:18 GMT, Kerem Kat <krk at openjdk.org> wrote:

>> The `help` command in `debug.cpp` was out of date, listing only a fraction of the available functions. This and other commands callable from gdb via `call help()`.
>> 
>> I added all commands to the help message, except `pns2` as it is documented as not being useful when called from gdb.
>> 
>> Also fixed is the message for the conditional `pns` command appearing in PRODUCT builds.
>
> Kerem Kat has updated the pull request incrementally with one additional commit since the last revision:
> 
>   address comments

As was mentioned previously, users of these functions should understand they are pretty much on their own, no guarantees...
But good to make it presentable where we can.

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Marked as reviewed by kevinw (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/27341#pullrequestreview-3251329180