Fix "git log --stat": make sure to set recursive with --stat.

Just like "patch" format always needs recursive, "diffstat"
format does not make sense without setting recursive.

Signed-off-by: Junio C Hamano <junkio@cox.net>

diff.c

@@ -1029,6 +1029,15 @@ int diff_setup_done(struct diff_options *options)
 	     options->detect_rename != DIFF_DETECT_COPY) ||
 	    (0 <= options->rename_limit && !options->detect_rename))
 		return -1;
+
+	/*
+	 * These cases always need recursive; we do not drop caller-supplied
+	 * recursive bits for other formats here.
+	 */
+	if ((options->output_format == DIFF_FORMAT_PATCH) ||
+	    (options->output_format == DIFF_FORMAT_DIFFSTAT))
+		options->recursive = 1;
+
 	if (options->detect_rename && options->rename_limit < 0)
 		options->rename_limit = diff_rename_limit_default;
 	if (options->setup & DIFF_SETUP_USE_CACHE) {

revision.c

@@ -791,8 +791,6 @@ int setup_revisions(int argc, const char **argv, struct rev_info *revs, const ch
 		if (revs->dense_combined_merges)
 			revs->diffopt.output_format = DIFF_FORMAT_PATCH;
 	}
-	if (revs->diffopt.output_format == DIFF_FORMAT_PATCH)
-		revs->diffopt.recursive = 1;
 	revs->diffopt.abbrev = revs->abbrev;
 	diff_setup_done(&revs->diffopt);