git-compat-util.h: use "UNUSED", not "UNUSED(var)"

As reported in [1] the "UNUSED(var)" macro introduced in
2174b8c75de (Merge branch 'jk/unused-annotation' into next,
2022-08-24) breaks coccinelle's parsing of our sources in files where
it occurs.

Let's instead partially go with the approach suggested in [2] of
making this not take an argument. As noted in [1] "coccinelle" will
ignore such tokens in argument lists that it doesn't know about, and
it's less of a surprise to syntax highlighters.

This undoes the "help us notice when a parameter marked as unused is
actually use" part of 9b240347543 (git-compat-util: add UNUSED macro,
2022-08-19), a subsequent commit will further tweak the macro to
implement a replacement for that functionality.

1. https://lore.kernel.org/git/220825.86ilmg4mil.gmgdl@evledraar.gmail.com/
2. https://lore.kernel.org/git/220819.868rnk54ju.gmgdl@evledraar.gmail.com/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 3 insertions, 3 deletions

diff --git a/walker.c b/walker.c
index f945d02..99d0e0e 100644
--- a/walker.c
+++ b/walker.c
@@ -215,10 +215,10 @@ static int interpret_target(struct walker *walker, char *target, struct object_i
 	return -1;
 }
 
-static int mark_complete(const char *UNUSED(path),
+static int mark_complete(const char *path UNUSED,
 			 const struct object_id *oid,
-			 int UNUSED(flag),
-			 void *UNUSED(cb_data))
+			 int flag UNUSED,
+			 void *cb_data UNUSED)
 {
 	struct commit *commit = lookup_commit_reference_gently(the_repository,
 							       oid, 1);