chore: [k210] fix: add logging to empty bloom

[grafanabot]

Backport c263a68 from #13502

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What this PR does / why we need it:
Follow up for #13500 to log the empty blooms with their block and offset.

I also moved the bloom empty check outside the reqs loop.

Special notes for your reviewer:

Checklist

• Reviewed the CONTRIBUTING.md guide (required)
• Documentation added
• Tests updated
• Title matches the required conventional commits format, see here
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