diff-index.c: do not pretend paths are pathspecs
diff-index.c: do not pretend paths are pathspecs

"git diff --no-index" takes exactly two paths, not pathspecs, and
has its own way queue_diff() to populate the diff_queue.  Do not
call diff_tree_setup_paths(), pretending as it takes pathspecs.

Signed-off-by: Junio C Hamano <a6723cc3f76163bf7adb636a73ac3b0ceb3e6b9b@pobox.com>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git