pathspec: convert some match_pathspec_depth() to dir_path_match()

This helps reduce the number of match_pathspec_depth() call sites and
show how m_p_d() is used. And it usage is:

 - match against an index entry (ce_path_match or match_pathspec_depth
   in ls-files)

 - match against a dir_entry from read_directory (dir_path_match and
   match_pathspec_depth in clean.c, which will be converted later)

 - resolve-undo (rerere.c and ls-files.c)

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/builtin/ls-files.c b/builtin/ls-files.c
index e1cf6d8..e238608 100644
--- a/builtin/ls-files.c
+++ b/builtin/ls-files.c
@@ -64,7 +64,7 @@
 	if (len >= ent->len)
 		die("git ls-files: internal error - directory entry not superset of prefix");
 
-	if (!match_pathspec_depth(&pathspec, ent->name, ent->len, len, ps_matched))
+	if (!dir_path_match(ent, &pathspec, len, ps_matched))
 		return;
 
 	fputs(tag, stdout);