[Bug] DFSv1 mount rw flags

[GuEe-GUI]

RT-Thread Version

all

Hardware Type/Architectures

all

Develop Toolchain

Other

Describe the bug

此处打开设备代码需要考虑设备只读情况，驱动开发者有权利在 open 阶段拒绝访问：

https://github.com/RT-Thread/rt-thread/blob/f4cb323919941c4d78fd2429f40789745ddc8e8c/components/dfs/dfs_v1/src/dfs_fs.c#L323-L337

Other additional context

No response