Revert "excluded_1(): support exclude files in index"

This reverts commit c84de70.
The commit provided a workaround for matching directories in
index. But it is no longer needed.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

dir.c

@@ -371,13 +371,6 @@ int excluded_from_list(const char *pathname,
 			int to_exclude = x->to_exclude;
 
 			if (x->flags & EXC_FLAG_MUSTBEDIR) {
-				if (!dtype) {
-					if (!prefixcmp(pathname, exclude) &&
-					    pathname[x->patternlen] == '/')
-						return to_exclude;
-					else
-						continue;
-				}
 				if (*dtype == DT_UNKNOWN)
 					*dtype = get_dtype(NULL, pathname, pathlen);
 				if (*dtype != DT_DIR)