Merge branch 'jk/plug-list-object-filter-leaks'

Merge branch 'jk/plug-list-object-filter-leaks'

The code that manages list-object-filter structure, used in partial
clones, leaked the instances, which has been plugged.

* jk/plug-list-object-filter-leaks:
  prepare_repo_settings(): plug leak of config values
  list_objects_filter_options: plug leak of filter_spec strings
  transport: free filter options in disconnect_git()
  transport: deep-copy object-filter struct for fetch-pack
  list_objects_filter_copy(): deep-copy sparse_oid_name field