RFR: 8310921: Fix -Wconversion warnings from GenerateOopMap [v2]

[Coleen Phillimore]

On Tue, 27 Jun 2023 13:20:21 GMT, Coleen Phillimore <coleenp at openjdk.org> wrote:

>> This is broken out from but tested with the PR from https://github.com/openjdk/jdk/pull/14659
>
> Coleen Phillimore has updated the pull request incrementally with one additional commit since the last revision:
> 
>   David Holmes comments

Thanks Ioi and David for reviewing.

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PR Comment: https://git.openjdk.org/jdk/pull/14666#issuecomment-1611303949