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, 1 insertions, 1 deletions

diff --git a/oidmap.c b/oidmap.c
index 32aeb0526f..49965fe856 100644
--- a/oidmap.c
+++ b/oidmap.c
@@ -1,7 +1,7 @@
 #include "cache.h"
 #include "oidmap.h"
 
-static int oidmap_neq(const void *UNUSED(hashmap_cmp_fn_data),
+static int oidmap_neq(const void *hashmap_cmp_fn_data UNUSED,
 		      const struct hashmap_entry *e1,
 		      const struct hashmap_entry *e2,
 		      const void *keydata)