tree.c: make read_tree*() take 'struct repository *'

These functions call tree_entry_interesting() which will soon require
a 'struct index_state *' to be passed in. Instead of just changing the
function signature to take an index, update to take a repo instead
because these functions do need object database access.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/merge-recursive.c b/merge-recursive.c
index acc2f64..b9467f5 100644
--- a/merge-recursive.c
+++ b/merge-recursive.c
@@ -463,7 +463,8 @@ static void get_files_dirs(struct merge_options *o, struct tree *tree)
 {
 	struct pathspec match_all;
 	memset(&match_all, 0, sizeof(match_all));
-	read_tree_recursive(tree, "", 0, 0, &match_all, save_files_dirs, o);
+	read_tree_recursive(the_repository, tree, "", 0, 0,
+			    &match_all, save_files_dirs, o);
 }
 
 static int get_tree_entry_if_blob(const struct object_id *tree,