The `git log -L` implementation has been refactored to use the
standard diff output pipeline, enabling pickaxe and diff-filter to
work as expected. Additionally, metadata-only diff formats like
--raw and --name-only are now supported with -L.
* mm/line-log-cleanup:
line-log: allow non-patch diff formats with -L
line-log: integrate -L output with the standard log-tree pipeline
revision: move -L setup before output_format-to-diff derivation