[fix](dfs): fix dfs path max

[Descriptions]:
    1. Current default DFS_PATH_MAX is 4096, but it should be DIRENT_NAME_MAX.

Author: PlainWaterK

components/dfs/dfs_v2/include/dfs.h

@@ -69,7 +69,7 @@
 #endif
 
 #ifndef DFS_PATH_MAX
-#define DFS_PATH_MAX            4096
+#define DFS_PATH_MAX            DIRENT_NAME_MAX
 #endif
 
 #ifndef SECTOR_SIZE