Add Kdump option to disable reboot after save_core

[nangelastro]

Merge Checklist

All boxes should be checked before merging the PR (just tick any boxes which don't apply to this PR)

• The toolchain has been rebuilt successfully (or no changes were made to it)
• The toolchain/worker package manifests are up-to-date
• Any updated packages successfully build (or no packages were changed)
• Packages depending on static components modified in this PR (Golang, *-static subpackages, etc.) have had their Release tag incremented.
• Package tests (%check section) have been verified with RUN_CHECK=y for existing SPEC files, or added to new SPEC files
• All package sources are available
• cgmanifest files are up-to-date and sorted (./cgmanifest.json, ./toolkit/scripts/toolchain/cgmanifest.json, .github/workflows/cgmanifest.json)
• LICENSE-MAP files are up-to-date (./LICENSES-AND-NOTICES/SPECS/data/licenses.json, ./LICENSES-AND-NOTICES/SPECS/LICENSES-MAP.md, ./LICENSES-AND-NOTICES/SPECS/LICENSE-EXCEPTIONS.PHOTON)
• All source files have up-to-date hashes in the *.signatures.json files
• sudo make go-tidy-all and sudo make go-test-coverage pass
• Documentation has been updated to match any changes to the build system
• Ready to merge

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Summary

What does the PR accomplish, why was it needed?

By default, Kdump copies the entire vmcore to the disk and reboots the
system afterwards. While this works in most cases, it does not work for
systems hosted in RAM where the crash dump will be lost once rebooted.
To support this scenario, a new option in the kdump.conf,
save_core_to_ram, is added and commented out. Setting this option to 1
will allow a compressed crash dump to be produced by utilizing the
core_collector option if specified, otherwise the dmesg log will be
extracted from the vmcore. This is especially necessary because there is
no disk to save the dump to, and there is not enough space in the
pre-allocated crashkernel memory space to save an entire vmcore.

Change Log

• kexec-tools

Does this affect the toolchain?

NO

Test Methodology

• Pipeline build id: 662082
• Full pipeline build id: 662087
• option permutation:
  • save_core_to_ram 0 => observe original behavior
  • save_core_to_ram 1 => system is not rebooted and a compressed crash dump is saved to /var/crash/<date>/vmcore

[nangelastro]

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[gjswalling]

please add new line at end of the file. I found description here: https://stackoverflow.com/a/77201456/22141712