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