[PATCH 08/22] stash: mark unused parameter in diff callback

This is similar to the cases in 61bdc7c5d8 (diff: mark unused parameters
in callbacks, 2022-12-13), but I missed it when making that commit.

Signed-off-by: Jeff King <redacted>
---
 builtin/stash.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/builtin/stash.c b/builtin/stash.c
index fe64cde9ce..c9365bea13 100644
--- a/builtin/stash.c
+++ b/builtin/stash.c

@@ -362,7 +362,7 @@ static int is_path_a_directory(const char *path)
 }
 
 static void add_diff_to_buf(struct diff_queue_struct *q,
-			    struct diff_options *options,
+			    struct diff_options *options UNUSED,
 			    void *data)
 {
 	int i;

-- 
2.42.0.505.g4c6fb48dec