diff_setup_done(): return void

diff_setup_done() has historically returned an error code, but lost
the last nonzero return in 943d5b7 (allow diff.renamelimit to be set
regardless of -M/-C, 2006-08-09).  The callers were in a pretty
confused state: some actually checked for the return code, and some
did not.

Let it return void, and patch all callers to take this into account.
This conveniently also gets rid of a handful of different(!) error
messages that could never be triggered anyway.

Note that the function can still die().

Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/tree-diff.c b/tree-diff.c
index 28ad6db..f760740 100644
--- a/tree-diff.c
+++ b/tree-diff.c
@@ -212,8 +212,7 @@
 	diff_opts.rename_score = opt->rename_score;
 	paths[0] = NULL;
 	diff_tree_setup_paths(paths, &diff_opts);
-	if (diff_setup_done(&diff_opts) < 0)
-		die("unable to set up diff options to follow renames");
+	diff_setup_done(&diff_opts);
 	diff_tree(t1, t2, base, &diff_opts);
 	diffcore_std(&diff_opts);
 	diff_tree_release_paths(&diff_opts);