Change: free report printing context using a function

[mattmundell]

What

In print_report_xml_start, Instead of freeing the zone data in tz_revert, free it with a new function.

Why

Eventually there will be more data in the struct, so it makes sense to free it all in one place. This also allows freeing the tz data in the success case, which was missing.

This is part of reducing the size of print_report_xml_start.

References

Follows /pull/2668.

Testing

I got a single report with the PR, then got the same report on the main branch. I made sure they were the same. I did that with two timezones just to be sure (using the timezone term in the filter).

o m m '<get_reports report_id="92a09ffd-a5bd-464b-9f2c-54b78ec5ebcf" details="1" filter="timezone=Pacific/Auckland rows=3 apply_overrides=1 min_qod=60"/>' > /tmp/r-auk-main
o m m '<get_reports report_id="92a09ffd-a5bd-464b-9f2c-54b78ec5ebcf" details="1" filter="timezone=Europe/Berlin rows=3 apply_overrides=1 min_qod=60"/>' > /tmp/r-ber-main
diff /tmp/r-auk /tmp/r-auk-main
diff /tmp/r-ber /tmp/r-ber-main

[mattmundell]

Thanks @robindittmar