clarify some error messages wrt unknown object types

If ever new object types are added for future extensions then better
have current git version report them as "unknown" instead of
"corrupted".
Signed-off-by: NNicolas Pitre <nico@cam.org>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

index-pack.c

@@ -266,7 +266,7 @@ static void *unpack_raw_entry(struct object_entry *obj, union delta_base *delta_
 	case OBJ_TAG:
 		break;
 	default:
-		bad_object(obj->offset, "bad object type %d", obj->type);
+		bad_object(obj->offset, "unknown object type %d", obj->type);
 	}
 	obj->hdr_size = consumed_bytes - obj->offset;
 

sha1_file.c

@@ -1013,7 +1013,7 @@ void packed_object_info_detail(struct packed_git *p,
 	for (;;) {
 		switch (kind) {
 		default:
-			die("corrupted pack file %s containing object of kind %d",
+			die("pack %s contains unknown object type %d",
 			    p->pack_name, kind);
 		case OBJ_COMMIT:
 		case OBJ_TREE:
@@ -1063,7 +1063,7 @@ static int packed_object_info(struct packed_git *p, unsigned long offset,
 		strcpy(type, type_names[kind]);
 		break;
 	default:
-		die("corrupted pack file %s containing object of kind %d",
+		die("pack %s contains unknown object type %d",
 		    p->pack_name, kind);
 	}
 	if (sizep)