diff --shortstat: do not count "unmerged" entries

Fix the same issue as the previous one for "git diff --stat";
unmerged entries was doubly-counted.

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

diff.c

@@ -1701,9 +1701,8 @@ static void show_shortstats(struct diffstat_t *data, struct diff_options *option
 		int added = data->files[i]->added;
 		int deleted= data->files[i]->deleted;
 
-		if (data->files[i]->is_unmerged)
-			continue;
-		if (!data->files[i]->is_interesting && (added + deleted == 0)) {
+		if (data->files[i]->is_unmerged ||
+		    (!data->files[i]->is_interesting && (added + deleted == 0))) {
 			total_files--;
 		} else if (!data->files[i]->is_binary) { /* don't count bytes */
 			adds += added;