t-hashmap: mark unused parameters in callback function

The t_intern() setup function doesn't operate on a hashmap, so it
ignores its parameters. But we can't drop them since it is passed as a
pointer to setup(), so we have to match the other setup functions. Mark
them to silence -Wunused-parameter.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: peff

t/unit-tests/t-hashmap.c

@@ -322,7 +322,8 @@ static void t_alloc(struct hashmap *map, unsigned int ignore_case)
 	free(removed);
 }
 
-static void t_intern(struct hashmap *map, unsigned int ignore_case)
+static void t_intern(struct hashmap *map UNUSED,
+		     unsigned int ignore_case UNUSED)
 {
 	const char *values[] = { "value1", "Value1", "value2", "value2" };