RFR: 8358515: make cmp-baseline is broken after JDK-8349665 [v2]

[Erik Joelsson]

On Tue, 3 Jun 2025 19:19:32 GMT, Magnus Ihse Bursie <ihse at openjdk.org> wrote:

>> The fix in to [JDK-8357991](https://bugs.openjdk.org/browse/JDK-8357991) was not enough to solve all problems that had been introduced with JDK-8349665. Also builds run using `COMPARE_BUILD` was affected.
>> 
>> The core of the problem was that there were multiple additional ways to run what esstentially amount to `make -f Init.gmk main`, in places that I did not find before. So I took a step back and chose a safer approach: now the `main` target in `Init.gmk` depends on an additional target, that will always make sure that the necessary helper files are present. This means the specific patch for bootcycle builds in JDK-8357991 could be reverted. This solution is also future-proof if we should figure out any new creative ways of calling `main` in `Init.gmk`.
>
> Magnus Ihse Bursie has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Fix indentation

Marked as reviewed by erikj (Reviewer).

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PR Review: https://git.openjdk.org/jdk/pull/25618#pullrequestreview-2893804265