[llvm] Define a separate symbol for the aot method info for every method. Pass this...

[llvm] Define a separate symbol for the aot method info for every method. Pass this symbol to the init functions instead of the method index. (#34009)

This removes a dependency the generated code has on the method index, hopefully allowing separate compilation etc. in the future.

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Co-authored-by: vargaz <vargaz@users.noreply.github.com>