hashmap: remove type arg from hashmap_{get,put,remove}_entry

Since these macros already take a `keyvar' pointer of a known type,
we can rely on OFFSETOF_VAR to get the correct offset without
relying on non-portable `__typeof__' and `offsetof'.

Argument order is also rearranged, so `keyvar' and `member' are
sequential as they are used as: `keyvar->member'

Signed-off-by: Eric Wong <e@80x24.org>
Reviewed-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/config.c b/config.c
index 77ed00b..a4fa464 100644
--- a/config.c
+++ b/config.c
@@ -1863,8 +1863,7 @@ static struct config_set_element *configset_find_element(struct config_set *cs,
 
 	hashmap_entry_init(&k.ent, strhash(normalized_key));
 	k.key = normalized_key;
-	found_entry = hashmap_get_entry(&cs->config_hash, &k, NULL,
-				struct config_set_element, ent);
+	found_entry = hashmap_get_entry(&cs->config_hash, &k, ent, NULL);
 	free(normalized_key);
 	return found_entry;
 }