Merge branch 'jk/unused-post-2.39' into maint-2.39

Code clean-up around unused function parameters. * jk/unused-post-2.39: userdiff: mark unused parameter in internal callback list-objects-filter: mark unused parameters in virtual functions diff: mark unused parameters in callbacks xdiff: mark unused parameter in xdl_call_hunk_func() xdiff: drop unused parameter in def_ff() ws: drop unused parameter from ws_blank_line() list-objects: drop process_gitlink() function blob: drop unused parts of parse_blob_buffer() ls-refs: use repository parameter to iterate refs